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\input{../include.tex}
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\begin{document}

\title{IGCSE Chemistry Notes}
\date{$2007$--$9$}
\author{Edward Lilley}

\maketitle
\tableofcontents
\listoftables
\listoffigures

\section{Introduction}


\subsection{Methods of Purification}

\begin{description}
\item [Filtration] to remove solid particles (bigger than clay sized
  ($<\frac{1}{256}\mr{mm}$)).
\item [Crystallisation] removes the solvent, to leave the solute.
\item [Fractional Distillation] produces a number of substances from
  the original mixture (e.g. petroleum).
\item [Sedimentation] allows an insoluble solid to separate out and
  sink to the bottom of a container
\item [Centrifuging] a spinning motion increases the force of gravity
  that quickly separates a solid from a suspension.
\item [Decanting] pouring off liquid (e.g. pouring off excess water
  from a pot of peas).
\item [Magnetic Separation] a method for separating one solid (usually
  iron) from a mixture of solids, Very useful for separating Aluminium
  cans from steel cans.
\end{description}

\subsubsection{Purification of Substances}

Materials that are produced to a high degree of purity give
predictable results (e.g. drugs, concrete).

Purity can be measured in a number of ways:

\begin{itemize}
\item melting point/boiling point
\item chromatography
\end{itemize}

\subsection{Measurement}

Purity is impossible without measurement. In science we use the MKS
system of units.

\begin{description}
\item [Time]
  \begin{itemize}
  \item measured in seconds
  \item clock, stopwatch, sundial, computer
    \begin{description}
    \item[Digital] one step at a time
    \item[Analogue] continuously changing
    \end{description}
  \item atomic clocks
  \end{itemize}
\item [Mass]
  \begin{itemize}
  \item measured in grams/kilograms
  \item scales (electronic), triple beam balance
  \end{itemize}
\item [Distance]
  \begin{itemize}
  \item measured in metres
  \end{itemize}
\item [Volume]
  \begin{itemize}
  \item cm$^{\text{3}}$, ml
  \item measuring cylinder, burettes, pipettes
  \end{itemize}
\item [Density]
  \begin{itemize}
  \item g/cm$^{\text{3}}$ $(\frac{mass}{volume})$
  \end{itemize}
\end{description}

\subsection{Water}

\begin{table}
  \begin{tabular}{lll}
    \hline
              & Air                                           & Water                                        \\ \hline
    Chemistry & \ce{N2}, \ce{O2}, \ce{Ar}, \ce{CO2}, \ce{H2O} & \ce{H2O}, dissolved salts, \ce{O2}, \ce{CO2} \\
    Density   & low                                           & high                                         \\ \hline
\end{tabular}
  \caption{Comparison of the chemistry of water and air.}
\end{table}

\paragraph{Testing for Water}

Cobalt Chloride (CoCl$_{2}$) turns pink in the presence of water (it
is blue when dry).

\paragraph{Uses of Water}

\begin{enumerate}
\item Home
  \begin{itemize}
  \item drinking
  \item washing
  \item putting out fires
  \item garden watering
  \item cooking
  \item heating
  \end{itemize}
\item Industry
  \begin{itemize}
  \item coolant
  \item lubricant
  \item dilutant
  \item additive
  \item solvent
  \item H.E.P.
  \end{itemize}
\end{enumerate}

\subsection{Air}


\paragraph{Uses of Components of Air}

\begin{description}
\item [Nitrogen] 79\% of air, used as a foaming agent e.g. packaging.
\item [Oxygen] 20\% of air, used in cutting torches (oxy-acetelene).
\item [Carbon~Dioxide] $\ll$1\% used in pneumatics, for putting out
  fires, special effects, coolant (dry ice).
\item [Argon] $\lll$1\%, in torch batteries and car headlights.
\end{description}
Note: The way to obtain any of these gases is by fractional
distillation at low temperatures.


\subsection{Carbon Dioxide}

\begin{itemize}
\item A gas at room temperature and pressure (RTP: 25\degc, 1 atm).
\item Colourless and odourless.
\item The standard test for \ce{CO2} is to pass it through limewater,
  and observer whether the limewater turns cloudy or not (if it does,
  then \ce{CO2} is present).
\item Industrial uses are:
  \begin{itemize}
  \item As a bubble generator in foams (foaming agent)
  \item Carbonated drinks
  \item \ce{CO2} enrichment in greenhouses to promote growth
  \item Fire extinguisher
  \item Refrigerant (dry ice)
  \end{itemize}
\item Sources of \ce{CO2}
  \begin{itemize}
  \item Respiration (cellular)
  \item Burning fuels (fossil fuels, bio-fuels, natural fires)
  \item Volcanoes
  \item Weathering of carbonate rocks.
  \end{itemize}
\end{itemize}

\subsection{States of Matter}

\begin{description}
\item [Solid] at a given temperature has a definite shape and
  volume. Heating causes this volume to expand and cooling causes
  contraction (shrinking).
\item [Liquid] at a given temperature, a liquid has a set volume but
  takes on the shape of its container.
\item [Gas] at a given temperature has neither a definite shape or a
  definite volume.
\end{description}

\begin{figure}[htb!]
\scalebox{1}{\includegraphics{states-of-matter}}
\caption{The 3 states of matter and associated processes.}
\end{figure}

\subsection{Kinetic Theory}

Kinetic Theory (or Particle Theory) states that all matter is made up
of particles. These particles vibrate with solids having the smallest
amount of vibration and gases having the most. As materials are
cooled, the particle vibration decreases and ceases at
$-273.15^{\circ}$C ($0^{\circ}$K), absolute zero.


\subsubsection{Evidence for Kinetic Theory}

\begin{description}
\item [Diffusion] diffusion is used as evidence of the particle theory
  because gas can be shown to diffuse at a much faster rate than
  diffusion in liquids e.g. perfume sprayed into one corner of a room
  will quickly spread through the room. Also, when Potassium
  Pomanganate (KMnO4) crystals diffusing in warm and cool water,
  respectively, are compared, it is shown that the KMnO4 diffuses
  considerably faster in the warm water. This supports kinetic theory
  in that the warmer particles have more energy, so they can diffuse
  faster.
\item [Brownian Motion] the apparent random movement of small
  particles. First observed in the early nineteenth century when
  pollen grains were observed to move in a random pattern on a water
  droplet. It is explained by the collision of water molecules with
  the pollen in a random pattern of collisions.
\end{description}

\subsection{Gas Laws}

\begin{itemize}
\item There is a relationship between the temperature of a gas and its
  volume.  Charles's law states that the volume of a gas is directly
  proportional to its temperature:

  \[V\propto T\]

  This can be rewritten to:

  \[\frac{V}{T}=constant\]

\item There is an inverse relationship between gas volume and
  pressure.  Boyle's law states that as the pressure on a gas
  increases its volume decreases:

  \[V\propto\frac{1}{P}\]

  This can be rewritten to:

  \[PV=constant\]

\end{itemize}

\subsubsection{Combined Gas Laws}

\[\frac{P_{1}V_{1}}{T_{1}}=\frac{P_{2}V_{2}}{T_{2}}\]
Combining the two laws produces this equation. If you change the
Pressure (P) or the Volume (V), it is easy to calculate the new
Temperature (T). $T_{1}$is old temperature, $T_{2}$is changed
temperature.

\section{Atomic Structure}

\subsection{Structure of the Atom}

\begin{itemize}
\item The atom is thought to be made up of a central nucleus that
  contains protons, and usually neutrons. The nucleus is surrounded by
  a ``cloud'' of electrons.
  \begin{itemize}
  \item Protons (p$^{+}$) have a positive charge.
  \item Neutrons (n$^{0}$) have no charge.
  \item Electrons (e$^{-}$) have a negative charge.
  \end{itemize}
\item The atomic number of an element defines which element you are
  looking at. This is determined by the number of protons (this is
  also the number of electrons). The atomic mass is the sum of the
  number of protons + neutrons in the nucleus.
\item It is possible to summarize this data using symbols. e.g.
\begin{itemize}
\item $_{1}^{1}$H = Hydrogen with 1p$^{+}$ and 1e$^{-}$ and no
  n$^{0}$.
\item $_{6}^{12}$C = Carbon with 6p$^{+}$ and 6e$^{-}$ and 6n$^{0}$.
\end{itemize}
\item The electrons and the protons balance each other so that an atom
  has no overall electric charge. The electrons are packed around the
  nucleus in a series of layers or shells.
\item The electrons fill up the shells progressively with:
  \begin{itemize}
  \item 2e$^{-}$ in the first shell
  \item 8e$^{-}$ in the second
  \item 8e$^{-}$ in the third
  \item 18e$^{-}$ in the fourth.
  \end{itemize}
\end{itemize}

\subsection{Sub-atomic Particles and Mass}

The neutron is the heaviest of the non-fundamental sub-atomic
particles.  It has a mass of about $1.675\times10^{27}kg$, slightly
more than the proton. It has no electronic charge, is located in the
nucleus of the atom, and is written as $n^{0}$. The next heaviest is
the proton, with a mass of about $1.673\times10^{27}kg$. It is located
in the nucleus of the atom, and has a positive electric charge of
$1.602\times10^{19}C$ (Coulombs). It is written as $P^{+}$. The
smallest sub-atomic particle (that is part of the atom itself) is the
electron, which is also a fundamental particle. It has a mass of
$9.109\times10^{31}kg$ (i.e. several orders of magnitude less than
both the neutron and the proton), and a negative electronic charge of
$1.602\times10^{19}C$. It is written as $e^{-}$.

\begin{sidewaystable}
%\begin{table}[htb!]
\begin{tabular}{|l||r|r|r|r|r|r|}
  \hline
  Element & Atomic Number (Z) & Mass Number (A) & No. of p$^{+}$ & No. of n$^{0}$ & No. of e$^{-}$ & Electron Configuration \\ \hline \hline
  H       & 1                 & 1               & 1              & 0             & 1              & 1                      \\ \hline
  He      & 2                 & 4               & 2              & 2             & 2              & 2                      \\ \hline
  Li      & 3                 & 7               & 3              & 4             & 3              & 2.1                    \\ \hline
  Be      & 4                 & 9               & 4              & 5             & 4              & 2.2                    \\ \hline
  B       & 5                 & 11              & 5              & 6             & 5              & 2.3                    \\ \hline
  C       & 6                 & 12              & 6              & 6             & 6              & 2.4                    \\ \hline
  N       & 7                 & 14              & 7              & 7             & 7              & 2.5                    \\ \hline
  O       & 8                 & 16              & 8              & 8             & 8              & 2.6                    \\ \hline
  F       & 9                 & 19              & 9              & 10            & 9              & 2.7                    \\ \hline
  Ne      & 10                & 20              & 10             & 10            & 10             & 2.8                    \\ \hline
\end{tabular}
\caption{The electron configuration of the first 10 elements.}
%\end{table}
\end{sidewaystable}

\begin{figure}[htb!]
\includegraphics[scale=0.75]{diagram-of-atom}
\caption{A diagram of a typical atom, with \ce{20n^0}, \ce{20p+} and \ce{20e-}.}
\end{figure}

$Z=20$

$A=40$

$e^{-}\approx1.602\times10^{-19}C$

$20\times e^{-}\approx-32.04\times10^{-19}C$ (Coulombs - measurement
of charge).


\subsection{Isotopes}

An isotope is an element that has a different number neutrons in its
nucleus. e.g.

\begin{itemize}
\item Hydrogen $_{1}^{1}$H
\item Deuterium $_{1}^{2}$H
\item Tritium $_{1}^{3}$H
\end{itemize}
The more common nomenclature (naming system) for isotopes gives the
element name followed by a number that is the atomic mas number. e.g.

\begin{itemize}
\item C12 = $_{6}^{12}$C
\item C13 = $_{6}^{13}$C
\item C14 = $_{6}^{14}$C
\end{itemize}
Isotopes can be radioactive or non-radioactive, The factor that
determines whether they are radioactive is if the neutron to proton
ratio is higher than 1.5:1.

\subsection{Uses of Isotopes}

\paragraph{Medical}

\begin{itemize}
\item Medical isotopes are used for treatment using radiation
  (radiotherapy).
\item Medical isotopes are used for imaging purposes (x-rays).
\item Medical isotopes are used to highlight soft tissues that cannot
  be imaged by x-rays.
\end{itemize}

\paragraph{Industrial}

\begin{itemize}
\item Isotopes can be used for ``on-line'' control of processes such
  as mining, metallurgy, mineral processing and welding checks.
\end{itemize}

\paragraph{Scientific}

\begin{itemize}
\item The decay of isotopes can be used to work out the age of rocks,
  fossils and earth processes such as plat collisions and fold
  mountain formation.
\end{itemize}

\subsection{Electronic Structure}

The number of electrons around an atom is the same as the number of
protons, The electrons `pack' around the nucleus in a series of
levels or shells. The strength of the electric charge on an electron
means that they pack around the nucleus in a pattern.

\begin{table}[htb!]
  \centering
 \begin{tabular}{lr}
   \hline
   Shell & No. of \ce{e-} \hfill \\ \hline
   1     & 2              \\
   2     & 8              \\
   3     & 8              \\
   4     & 18             \\
   5     & 18             \\
   6     & 32             \\ \hline
  \end{tabular}
  \caption{Electronic structure for the first 6 shells.}
\end{table}

All elements with the same number of electrons in their outer shell
(the valence electrons) will behave in a similar manner chemically.


\subsection{Valencies}

\begin{itemize}
\item Each of the groups in the periodic table have a distinctive
  valency.
\item The valency of an element (or radical) is the number of
  electrons available or electrons spaces that need to be filled.
\end{itemize}

\begin{table}[htb!]
  \centering
  \begin{tabular}{lrc}
    \hline
    Group & No. of e$^{-}$ in outer shell & Valency \\ \hline
    I     & 1                             & $1+$    \\
    II    & 2                             & $2+$    \\
    III   & 3                             & $3+$    \\
    IV    & 4                             & $4\pm$  \\
    V     & 5                             & $3-$    \\
    VI    & 6                             & $2-$    \\
    VII   & 7                             & $1-$    \\
    0     & 8                             & $0$     \\ \hline
  \end{tabular}
  \caption{Group valencies.}
\end{table}

Valencies 1+ to 3+, and 3- to 1-, form ionic bonds. 4+/- forms covalent
bonds, and 3- can form covalent forms sometimes, as well as ionic.

\begin{itemize}
\item For the transition metals, assume they have a valency of +2 with
  the notable exceptions being Fe(III) which has a valency of +3, and
  Hg(I) which has a valency of +1.
\item Radicals behave as if they were single atoms.
\end{itemize}

\begin{table}
  \centering
  \begin{tabular}{lll} \hline
    Radical Name       & Formula   & Valency \\ \hline
    Sulphate           & \ce{SO4}  & $-2$    \\
    Nitrate            & \ce{No3}  & $-1$    \\
    Carbonate          & \ce{CO3}  & $-2$    \\
    Phosphate          & \ce{PO4}  & $-3$    \\
    Hydrogen Carbonate & \ce{HCO3} & $-1$    \\
    Hydroxide          & \ce{OH}   & $-1$    \\
    Ammonium           & \ce{NH4}  & $+1$    \\ \hline
  \end{tabular}
  \caption{Valencies of common radicals.}
\end{table}

\section{Periodic Table \& Properties of Elements}

\subsection{What is the Periodic Table?}

It is a summary of all the known elements. The elements are arranged
in ascending order according to atomic number (Z). The vertical
columns are called groups and contain elements that have similar
chemical properties (dictated by the electron arrangement of the outer
shell).  The horizontal rows, or periods, show changing chemical
properties across a series of elements as their outer electron shell
fills up.


\subsection{History of the Periodic Table}

In 1817 Johann D\"{o}bereiner noticed that the atomic mass of
Strontium fell between that of Calcium and Barium, and all three had
similar chemical properties. He called this a ``triad'' of elements
and found three triads altogether:

\begin{itemize}
\item Calcium, Strontium, Barium
\item Chlorine, Bromine, Iodine
\item Lithium, Sodium, Potassium
\end{itemize}
In 1865, John Newlands listed all of the known elements by atomic mass
and noted that every eighth element had similar chemical properties.
He called this the ``Law of Octaves''.


\subsection{Group I -- The Alkali Metals}

($\downarrow$progressively more vigorous)

\[2Li_{(s)}+2H_{2}O_{(l)}\longrightarrow2LiOH_{(aq)}+H_{2(g)}\]


\[2Na_{(s)}+2H_{2}O_{(l)}\longrightarrow2NaOH_{(aq)}+H_{2(g)}\]


\[2K_{(s)}+2H_{2}O_{(l)}\longrightarrow2KOH_{(aq)}+H_{2(g)}\]


Each of these elements (Li, Na, K) have the same outer shell of
electrons (only 1e$^{-}$). This means that they combine with water in
the same way; two atoms of the elements in question will combine with
two molecules of water to form two molecules of the alkali salt of
that element and hydrogen gas. Each reaction is progressively more
vigorous (the reaction takes place in water). This group is known as
the alkali metals.

All of these metals react in a similar way because they have a similar
electron configuration i.e. they have a single electron in their outer
shell.

The reason for the increasing activity of the Group I metals down the
group is due to the position of the outer electron, As you go further
down the group, this single outer electron has a smaller attractive
force to the protons in the nucleus. e.g.

\begin{figure}[htb!]
  \centering
  \includegraphics[scale=0.8]{diagram-of-lithium-atom}
  \caption{A diagram of a Lithium atom (Li).}
\end{figure}

\begin{figure}[htb!]
  \centering
  \includegraphics[scale=0.8]{diagram-of-sodium-atom}
  \caption{A diagram of a Sodium atom (Na).}
\end{figure}

\begin{figure}[htb!]
  \centering
  \includegraphics[scale=0.8]{diagram-of-potassium-atom}
  \caption{A diagram of a Potassium atom (K).}
\end{figure}

\subsection{Group VII -- The Halogens}

\begin{itemize}
\item They are all reactive non-metals.
\item Fluorine is the most reactive while Iodine is the most stable
  i.e. stability increases down the group.
\item They are all coloured, with intensity of colour increasing down
  the group.
\item Their state at R.T.P. changes down the group with both Fluorine
  and Chlorine being gases, Bromine is a liquid and Iodine is a solid.
\item All of the Halogens are highly reactive, particularly with
  Groups I and II metals. They all combine with water to form strong
  acids.
  \begin{itemize}
  \item HF, Hydrofluoric acid
  \item HCl, Hydrochloric acid
  \item HBr, Hydrobromic acid
  \item HI, Hydroiodic acid
  \end{itemize}
\item Fluorine, a pale yellow gas, is used in the form of fluorides in
  drinking water and toothpaste because it reduces tooth decay by
  hardening the enamel on teeth.
\item Chlorine, a pale green gas, is used to make PVC plastic as well
  as household bleaches. It is also used to kill bacteria and viruses
  in drinking water.
\item Bromine, a brown liquid, is used to make disinfectants,
  medicines and fire retardants.
\item Iodine, a purple/black solid, is used in medicines and
  disinfectants and also as a photographic chemical.
\item Astatine is a radioactive black solid.
\end{itemize}

\subsection{Group 0 -- The Noble Gases}

These are Helium, Neon, Argon, Krypton, Xenon and Radon. They are all
gases, exist as single atoms, colourless, and strongly unreactive.
The only element in the group that forms compounds is Xenon, and this
can combine with fluorine to form XeF$_{6}$.

\begin{description}
\item[Helium] an inert lifting gas
\item[Argon] used in lights
\item[Neon] used in LASERs
\item[Xenon] % ... ???
\end{description}

\subsection{The Transition Elements}

\begin{itemize}
\item The transition elements are a group of metals that occur in the
  central panel of the periodic table and include elements:
  \begin{itemize}
  \item 21$\rightarrow$30
  \item 39$\rightarrow$48
  \item 57$\rightarrow$80
  \item 89$\rightarrow$112
  \end{itemize}
\item They have a number of features in common:
  \begin{itemize}
  \item High densities
  \item High melting and boiling points
    \begin{itemize}
    \item except Mercury (Hg)
    \end{itemize}
  \item They form strongly coloured compounds
  \end{itemize}
\item They often act as catalysts in reactions e.g.
  \begin{itemize}
  \item Pt
  \item Fe
  \item Co
  \end{itemize}
\item
\end{itemize}

\subsection{Bits and Pieces}

\begin{itemize}
\item Metal oxides will form basic (alkali) solutions when mixed with
  water.
\item Non-metal oxides will form acidic solutions when mixed with
  water.
\item An oxide that forms a neutral solution when mixed with water is
  called amphoteric.
\item The position of an element in the group is determined by the
  number of electrons in its outer shell.
\end{itemize}

\section{The Mole Concept}

\subsection{Size of Atoms}

Atoms have only recently been actually observed. They are often
smaller than 10$^{-30}$m.


\subsection{Avagadro's Constant}

A convenient way of calculating the number of moles is to use
Avagadro's constant ($N_{A}$):

\[N_{A}\approx6.023\times10^{23}mol^{-1}\]

Or more simply:\[ 6\times10^{23}\]

\subsection{Calculating Formulae}

\paragraph{Example 1}

If we were to combust some Magnesium ribbon in air, with careful
calculations and measurements we can calculate the formula of the
compound formed.

If we started with 0.24g of Mg and ended up with 0.40g of Magnesium
Oxide, we can work out the formula of the product.

\begin{table}[htb!]
  \centering
  \begin{tabular}{|l|ll|}
    \hline
    Element      & Mg   & O    \\ 
    Masses       & 0.24 & 0.16 \\
    No. of Moles & $\frac{0.24}{24g}=0.01$ & $\frac{0.16}{16g}=0.01$ \\
    \hline
  \end{tabular}
  \caption{Results of combustion of Magnesium.}
\end{table}

$\therefore$ formula $=$ \ce{MgO}.

\paragraph{Example 2}

An unknown chemical contains 0.12g of Carbon and 0.02g of Hydrogen.

\begin{table}[htb!]
  \centering
  \begin{tabular}{|l|ll|}
    \hline
    Element      & C    & H    \\
    Masses       & 0.12 & 0.02 \\
    No. of Moles & $\frac{0.12}{12g}=0.01$ & $\frac{0.02}{1g}=0.02$\\
    \hline
  \end{tabular}
  \caption{Results of combustion of an unknown chemical.}
\end{table}

$\therefore$ formula $=$ \ce{CH2}.

This is an empirical formula.

A mass spectrometer is used and the relative molecular mass is found
to be 56g.

If the empirical formula is calculated as a mass then \ce{CH2} would
have a mass of 14g.

Calculation: $\frac{56g}{14g}=4$.

$\therefore$ actual formula $=$ \ce{C4H8}.

\section{Formulae and Equations}

\subsection{Stoichiometry}

\begin{itemize}
\item Stoichiometry is the measurement of equations to make sure that
  they balance (law of conservation of mass). E.g.:
\item \ce{CaCO3} will break down into \ce{CaO} and \ce{CO2}.
  \[\ce{CaCO3_{(s)}} \longrightarrow \ce{CaCO_{(s)}} + \ce{CO2_{(g)}}\]
\item $100g\longrightarrow56g+44g$
\item $\ce{2H2} + \ce{O2} \rightarrow \ce{2H2O}$
\item $\frac{2.00{\mr{g}\ce{NaCl}}}{58.44{\mr{g}\ce{NaCl}\mr{mol}}^{-1}}=0.034\ mol$
\end{itemize}

\subsection{Group I}

\begin{itemize}
\item They form highly stable compounds.
  \begin{itemize}
  \item They have a valency of +1 because they form ions by losing an
    electron.
  \item All compounds of Group I elements are soluble in water. (Most
    Group VII are.)
  \item Group I metals are all light grey metals.
  \item The formulae of Group I compounds depends on the valency of
    the anion (negatively charged ion) they are attached to. e.g.
    \begin{itemize}
    \item Anions with $-1$ valency
      \begin{itemize}
      \item \ce{NaCl}
      \item \ce{NaI}
      \item \ce{NaNO3}
      \end{itemize}
    \item Anions with $-2$ valency
      \begin{itemize}
      \item \ce{Na2CO3}
      \item \ce{NA2So4}
      \item \ce{Na2O}
      \end{itemize}
    \item Anions with $-3$ valency
      \begin{itemize}
      \item \ce{Na3PO4}
      \end{itemize}
    \item Anions with $-4$ valency
      \begin{itemize}
      \item \ce{Na4C} (Sodium Carbide)
      \end{itemize}
    \end{itemize}
  \end{itemize}
\end{itemize}

\subsection{Group VII}

\begin{itemize}
\item Formulae of Group VII element compounds are determined by the valency
of the cation (positively charged ion) they are attached to. e.g.
  \begin{itemize}
  \item Cations with a +1 valency
    \begin{itemize}
    \item NaCl
      \begin{itemize}
      \item NH$_{4}$I
      \end{itemize}
    \item Cations with a +2 valency
      \begin{itemize}
      \item CaCl$_{2}$
      \item PbF$_{2}$
      \end{itemize}
    \item Cations with a +3 valency
      \begin{itemize}
      \item AlI$_{3}$
      \item GaCl$_{3}$
      \end{itemize}
    \end{itemize}
  \end{itemize}
\end{itemize}

\subsection{Hydrocarbons}

\beqn
\ce{2C2H6} + \ce{7O2} & \longrightarrow & \ce{4CO2} + \ce{6H2O} \\
\ce{2C8H18} + \ce{25O2} & \longrightarrow & \ce{16CO2} + \ce{16H2O} \\
\ce{C6H12O6} + \ce{6O2} & \longrightarrow & \ce{6CO2} + \ce{6H2O} \\
\ce{C12H22O11} + \ce{12O2} & \longrightarrow & \ce{12CO2} + \ce{11H2O} \\
\ce{CH4O6} + \ce{2O2} & \longrightarrow & \ce{CO2} + \ce{2H2O} \\
\ce{2C2H6O2} & \longrightarrow & \ce{4CO2} + \ce{6H20} \\
\ce{C3H8O6} + \ce{5O2} & \longrightarrow & \ce{3CO2} + \ce{4H2O} \\
\ce{2C4H10} + \ce{36O2} & \longrightarrow & \ce{8CO2} + \ce{10H2O} \\
\ce{C5H12} + \ce{8O2} & \longrightarrow & \ce{5CO2} + \ce{6H2O}
\eeqn



\section{Ionic Bonding}


\section{Covalent Bonding}


\section{Limestone}


\subsection{Introduction}

\begin{itemize}
\item The main mineral in Limestone is $CaCO_{3}$ or Calcite.
\item Lime-rich rocks might be called limestone, chalk or marble.
\end{itemize}

\subsection{Uses of Carbonate Rocks}

\begin{itemize}
\item Building stone

\begin{itemize}
\item as a structural unit i.e. columns or blocks in 'classical' buildings
\item as a decorative stone i.e. 'dressing stone'
\end{itemize}
\end{itemize}

\section{Metals}


\subsection{Properties of metals}

\begin{itemize}
\item Physical properties

\begin{itemize}
\item Usually solid at RTP.
\item When struck they will produce a ring tone.
\item Ductile: they can be drawn out into a wire.
\item Malleable: they take on the shape of an object that hits them.
\item Good conductor of heat.
\item Good conductor of electricity.
\item Most metals have a shiny surface when clean (or cut) (metallic lustre).
\item Most have a high density ($=\frac{mass}{volume}$).
\item High melting/boiling point.
\end{itemize}
\item Chemical properties
  \begin{itemize}
  \item Metals + dilute acids: any metal above copper in the reactivity series
    will react with an acid to produce a soluble salt of hydrogen gas
    e.g.

    \[ \ce{2HCl_{(aq)}}+\ce{Mg_{(s)}} \longrightarrow \ce{MgCl2_{(aq)}} + \ce{H2_{(g)}} \]

  \item Metals react with oxygen to form metal oxides e.g.

    \[ \ce{2Fe_{(s)}}+\ce{O2_{(g)}} \longrightarrow \ce{2FeO_{(s)}} \]

    Note: With the exception of Group I metal oxides, all other oxides
    are insoluble.

  \item Metals high in the reactivity series react readily with water
    (down to Mg) to produce hydrogen gas + a metal hydroxide.
  \end{itemize}
\end{itemize}



\subsection{Metallic Bonding}

\begin{itemize}
\item Metals have their own type of bonding that is quite different
  from ionic or covalent bonding.
\item Metallic bonds are fairly strong bonds, shown by the fact that
  with one exception, all metals are solids at RTP.
\item The arrangement of the metal is as a lattice with the individual
  atoms surrounded by large numbers of delocated electrons.
\item These delocalised electrons mean that electric current can be
  conducted through the structure.
\end{itemize}

\begin{figure}[htb!]
  \centering
  \includegraphics[scale=1.2]{dc-current}
  \caption{A representation of DC (direct current).}
\end{figure}

\begin{figure}[htb!]
  \centering
  \includegraphics[scale=1.2]{ac-current}
  \caption{A representation of AC {alternating current}.}
\end{figure}

\begin{sidewaystable}
  \begin{tabular}{|l|p{4cm}p{4cm}p{4cm}p{4cm}|}
    \hline
    Reactivity Series & Reaction with Dilute Acid              & Reaction with Air/Oxygen                     & Reaction with Water                                  & Ease of Extraction         \\ \hline
    Potassium (K)     & Produce \ce{H2} with decreasing vigour & Burn very brightly and vigourously           & Produce \ce{H2} with decreasing vigour in cold water & Difficult to extract       \\
    Sodium (Na)       & $\downarrow$                           & $\updownarrow$                               & $\downarrow$                                         & $\updownarrow$             \\
    Calcium (Ca)      & $\downarrow$                           & Burn to form an oxide with decreasing vigour & React with steam with decreasing vigour              & Easier to extract          \\
    Magnesium (Mg)    & $\downarrow$                           & $\downarrow$                                 & $\downarrow$                                         & $\downarrow$               \\
    Aluminium (Al)    & $\downarrow$                           & $\downarrow$                                 & $\downarrow$                                         & $\downarrow$               \\
    Carbon (C)        & $\downarrow$                           & $\downarrow$                                 & $\downarrow$                                         & $\downarrow$               \\
    Zinc (Zn)         & $\downarrow$                           & $\downarrow$                                 & $\downarrow$                                         & $\downarrow$               \\
    Iron (Fe)         & $\downarrow$                           & $\downarrow$                                 & $\downarrow$                                         & $\downarrow$               \\
    Lead (Pb)         & $\downarrow$                           & React slowly to form the oxide               & Do not react with water or steam                     & $\downarrow$               \\
    Copper (Cu)       & Do not react with dilute acids         & $\downarrow$                                 & $\updownarrow$                                       & $\downarrow$               \\
    Silver (Ag)       & $\updownarrow$                         & Do not react                                 & $\updownarrow$                                       & Found as element in nature \\
    Gold (Au)         & $\updownarrow$                         & $\updownarrow$                               & $\updownarrow$                                       & $\updownarrow$             \\
    Platinum (Pt)     & $\updownarrow$                         & $\updownarrow$                               & $\updownarrow$                                       & $\updownarrow$             \\ \hline
  \end{tabular}
  \caption{The Reactivity Series}
\end{sidewaystable}


\subsection{Alloys}

The reason for using alloys is that we can tailor the properties of
the metal to specific purposes. It is a crystal lattice like an
elemental metal, but the lattice is irregular because the atoms are of
different sizes.

\begin{figure}
  \centering
  \includegraphics[scale=2.2]{alloy-crystal-lattice}
  \caption{The crystal lattice of an alloy.}
\end{figure}

\subsection{Competition Reactions in Aqueous Solutions}

\begin{itemize}
\item If a metal from high in the reactivity series is placed in an
  aqueous solution of a metal from lower in the series then the first
  metal will displace the second. e.g.:
  \begin{itemize}
  \item \[\ce{Mg_{(s)}} + \ce{CuSO4_{(aq)}}    \longrightarrow \ce{Cu_{(s)}}        + \ce{MgSO4_{(aq)}}\]
  \item \[\ce{MG_{(s)}} + \ce{Cu{(aq)}}       \longrightarrow \ce{Mg_{(aq)}}       + \ce{Cu_{(s)}}    \]
  \item \[\ce{Zn_{(s)}} + \ce{Pb(NO3)2_{(aq)}} \longrightarrow \ce{Zn(NO3)2_{(aq)}} + \ce{Pb_{(s)}}    \]
  \end{itemize}
\item Most metal hydroxides are insoluble (the exceptions being the
  Group I metals) so an easy way to test for the presence of metal
  ions in solution is to add a few drops of $NaOH$. A coloured
  precipitate often forms.
\end{itemize}

\subsection{Aluminium -- The Problem Metal}


\section{Organic Fuels}


\subsection{Sources of fuels}

\begin{itemize}
\item The main source of combustible fuels is either petroleum or gas.
\item The main sources of petroleum are from OPEC countries, the North
  Sea, Russia and Bass Strait.
\item The method of recovering usable portions involves a process
  known as catalytic cracking where the petroleum is heated in a
  furnace then pumped into a tower structure and allowed to cool.
\item The various fractions obtained have different numbers of carbon
  atoms in a chain.
  \begin{itemize}
  \item A chain of $C_{1{\rightarrow}5}$ is a gas.
  \item $C_{6{\rightarrow}20}$ are liquids.
  \item $C_{>20}$ is a solid. (All at R.T.P.)
  \end{itemize}
\item The carbon atoms are mostly joined to hydrogen atoms so they are
  called hydrocarbons.
\item Fuels are generally burned. As such the chemical reaction is a
  combustion reaction.
\item The products of a combustion reaction, where complete reaction
  occurs, are $\ce{CO2} + \ce{H2O}$.
\end{itemize}


\section{Acids, Bases \& Salt Preparations}

\subsection{Oxygen \& Oxides}

Oxygen is a colourless odourless gas which is essential to life as we
know it on this planet. Oxygen is the second most abundant gas in the
air (21\%). It is also found in many different compounds in the
earth's crust, making it the most abundant elemsnt there also at 34\%
(silicon is next at 26\%).

When an element or a compound reacts with oxygen it is said to have
undergone an oxidisation (or combustion) reaction. If the reaction
involves a flame then it is called burning.

The products of these reactions of elements or compounds with oxygen
are \textsc{Oxides}. Both elements and compounds burn in pure oxygen
more fiercely than in air, because pure oxygen contains no nitrogen
which is a suppressor of reactions.

Examples of oxidations:

\[ \ce{4K + O2 {\longrightarrow} 2K2O} \]

\[ \ce{S + O2 {\longrightarrow} SO2} \]

\[ \ce{4Fe + 3O2 {\longrightarrow} 2Fe2O3} \]

\[ \ce{4NH3 + 7O2 {\longrightarrow} 4NO2 + 6H2O} \]

\[ \ce{2H2S + 3O2 {\longrightarrow} 2SO2 + 2H2O} \]

\subsection{Properties of the Oxides of the Elements}

Oxides of the elements can be made by burning the elements in oxygen.

Oxides which react with acids are called \textsc{Basic} oxides. Some
basic oxides are soluble in water. When they dissolve they form a
solution whose pH is greater than 7 (full range indicator turns from
green to blue). These soluble basic oxides are called
\textsc{Alkaline} oxides.

Oxides which dissolve in water to give a solution whose pH is less
than 7 (full range indicator turns from green to orange or red) are
\textsc{Acidic} oxides.

Some oxides are insoluble in water. If they are soluble in acids the
yare basic oxides. If they are soluble in alkalis they are acidic
oxides.

A few oxides are insoluble in water but soouble in both acids and
alkalis. They show both acidic and basic properties and are called
\textsc{Amphoteric} oxides.

Metallic elements on the left-hand-side of the Periodic Table form
\textsc{Basic} oxides; non-metallic elemnts on the right-hand-side of
the Periodic Table form \textsc{Acidic} oxides.

\subsection{Acids, Bases \& Salts}


Acids and alkalis (soluble bases) are a constant part of everyday
life. The most well-known acid-containg substance is probably vinegar,
but there are many others that we come across every day.
\begin{table}
  \centering
  \scalebox{0.9}{\begin{tabular}{ll|ll}\hline
      \multicolumn{2}{|c||}{\textbf{Acids}}    & \multicolumn{2}{c|}{\textbf{Alkalis}}          \\ \hline
      Vinegar                   & Acetic       & Garden lime       & Calcium (Hydr)Oxide        \\
      Fizzy drinks              & Ascorbic     & Oven cleaner      & Sodium/Potassium Hydroxide \\
      Rust remover              & Phosphoric   & Soap              & Potassium Hydroxide        \\
      Fruit juice               & Citric       & Household cleaner & Sodium Hydroxide/Ammonia   \\
      Kettle descaler           & Hydrochloric & Baking soda       & Sodium Hydrogen Carbonate  \\
      (Car) Battery acid        & Sulphuric    & Washing soda      & Sodium Carbonate           \\
      Fertilisers \& Explosives & Nitric       & Milk of Magnesia  & Magnesium/Sodium Carbonate \\
      TCP                       & Phosphoric   &                   &                            \\
      Fabric softeners          & Sorbic       &                   &                            \\ \hline
    \end{tabular}}
  \caption{Some common uses of Acids and Alkalis.}
\end{table}

The word `acid' means sharp or sour --- acids are known for their
characteristic sour taste. Lemon juice, uncorked wine, and milk that
has gone off all contain acids.

Acids and alkalis were found to change the colour of some plant
pigments. The colour extracted from red cabbage and from lichens have
different colours in acidic and alkaline solution. The indicator
derived from lichen is called \textsc{Litmus}, and goes red in acid
and blue in alkalis. \textsc{Full-range Indicator} (similar to
\textsc{Universal Indicator}) is a mixture of indicators, which can
show how strongly acidic or alkaline a substance is.

These substances which change colour when placed in acids and alkalis
are called \textsc{Indicators}.

The effects of acids can be removed by alkalis --- this kind of
reaction is called a \textsc{Neutralisation} reaction.

The properties of acidic and alkaline solutions are best explained in
terms of the ions which they contain.

An \textsc{Acid} is a compound which in aqueous solution produces
hydrogen ions \ce{H+}.

An \textsc{Alkali} is a compound which in aqueous solution produces
hydroxyl ions \ce{OH-}.

Acids, when pure, are composed of molecules. It is only in the
presence of water that they release hydrogen ions. (In fact, each
\ce{H+} ion which is set free bonds to a water molecule forming the
ion \ce{H3O+}.)

\textsc{Strong Acids} are almost totally broken down into ions in
aqueous solution (fully dissociated) e.g.\ \ce{Hcl}, \ce{HNO3},
\ce{H2SO4}.

\textsc{Weak Acids} are only partly broken down into ions when in
aqueous solution e.g.\ \ce{CH3CO2H} (ethanoic acid).

\[ \ce{CH3CO2H + H2O {\rightleftharpoons} CH3CO2- + H3O+} \]

\begin{table}
  \begin{tabular}{|l|c|c|c|}
    \hline
    Name & Formula & Ionic Formula & Strong or Weak? \\ \hline
    Hydrochloric acid & \ce{HCl} & \ce{H+ / Cl-} & S \\
    Sulphuric acid & \ce{H2SO4} & \ce{2H+ / SO_4^2-} & S \\
    Nitric acid & \ce{HNO3} & \ce{H+ / NO3-} & S \\
    Acetic or Ethanoic acid & \ce{CH3CO2H} & \ce{H+ / CH3CO2-} & W \\
    Citric acid & \ce{C6H8O7} & \ce{3H+ / C6H5O7^{3-}} & W \\ \hline
  \end{tabular}
  \caption{Important Acids}
\end{table}

\begin{table}
  \begin{tabular}{|l|c|c|c|}
    \hline
    Name & Formula & Ionic Formula & Strong or Weak? \\ \hline
    Sodium hydroxide & \ce{NaOH} & \ce{Na+ / OH-} & S \\
    Calcium hydroxide & \ce{Ca(OH)2} & \ce{Ca^2+ / 2OH-} & S \\
    Magnesium hydroxide & \ce{Mg(OH)2} & \ce{Mg^2+ / 2OH-} & S \\
    Sodium Hydrogen carbonate & \ce{NaHCO3} & \ce{Na+ / HCO3-} & W \\
    Ammonia (hydroxide) & \ce{NH4OH} & \ce{NH4+ / OH-} & W \\ \hline
  \end{tabular}
  \caption{Important Bases}
\end{table}

\subsubsection{The Role of Water}

Acids are covalently-bonded molecules.

E.g.\ Hydrogen Chloride (\ce{HCl}).

\begin{table}[htb!]
  \centering
  \begin{tabular}{r|ll}
    \hline
    & \ce{HCl} in \ce{H2O}          & \ce{HCl} in organic solvent  \\ \hline
    Temperature Change        & Marked rise                   & Little change                \\
    Reaction with \ce{Mg}     & Fizzes and \ce{Mg} disappears & No reaction                  \\
    Reaction with marble      & Fizzes and marble disappears  & No reaction                  \\
    Electrical conductivity   & Yes                           & No                           \\
    Universal indicator paper & Dark red                      & No change of colour          \\ \hline
  \end{tabular}
  \caption{Reactions of \ce{HCl}.}
\end{table}

\[ \ce{HCl_{(g)} + H2O_{(l)} {\longrightarrow} H3O+_{(aq)} + Cl-_{(aq)}} \]

The molecules dissociate into ions.

Atoms form ions in water. One of these ions is \ce{H+_{(aq)}}. The pH
is a measure of the strength of an acid or alkali, i.e.\ how much it
dissociates into ions when put in water.

\subsection{Salt Preparations}

To obtain pure samples of soluble salts it is necessary to ensure that
all of the acid has been used up in the reaction and that no excess of
the other reagent is left to contaminate the product.

\begin{enumerate}
\item An excess of solid is added to the acid to make sure all the
  acid is used up.
\item The excess solid is filtered off.
\item Salt srystals are then produced by evaporation and
  crystallisation:
  \begin{enumerate}
  \item The dilute solution of the salt is evaporated first directly
    then slowly over a steam bath.
  \item The solution is tested for saturaion by removing a droplet of
    the solution on a glass rod.
  \item If crystals form quickly when the droplet is cooled, then the
    solution is left to crystallise.
  \item If crystals do not form quickly evaporation is continued until
    the solution is saturated
  \end{enumerate}
\end{enumerate}

\subsection{Ionic Equations}

Many chemical reactions involve ionic substances. Ionic formulae can
be shown in the equation for the reaction. In these equations the
numbers of atoms and the charges on both sides must balance.

\subsubsection{Acids Reacting With Bases}

Many insoluble metal oxides react with dilute acids to form soluble salts.

\[ \ce{General\:equation{:\;\;} Base + Acid {\longrightarrow} Salt + Water} \]

\[ \ce{Word\: equation{:\;\;} Copper(II)\: oxide{(s)} + Hydrochloric\: acid{(aq)} {\longrightarrow} Copper(II)\: chloride{(aq)} + water{(l)} } \]

\[ \ce{Ordinary\: equation{:\;\;} CuO + 2HCl {\longrightarrow} CuCl2 + H2O } \]

\[ \ce{Ionic\: equation{:\;\;} CuO + 2H+ + 2Cl- {\longrightarrow} Cu^{2+} + 2Cl- + H2O } \]

Here O and H ions are spectator ions, so the ionic equation could be
written as:

\[ \ce{O^{2-} + 2H+ {\longrightarrow} H2O } \]

However, the Cu ions change from being solid to aqueous, so it is
usual to include them in the final ionic equation. It is also usual to
write the base as a molecular formula.

\[ \ce{Ionic\: equation{:\;\;} CuO + 2H+ {\longrightarrow} Cu^{2+} + H2O } \]

\subsubsection{Acids Reacting With Carbonates}

Carbon dioxide is given off when any dilute acid reacts with any
carbonate at room temperature.

\beqn
  \mr{General \: equation:} \; \; \mr{Carbonate} + \mr{Acid}            & \longrightarrow & \mr{Salt} + \mr{Carbon \: dioxide} + \mr{Water} \\
  \mr{Word \: equation:} \; \; \mr{Calcium \: carbonate(s)} + \mr{Hydrochloric \: acid(aq)} & \longrightarrow & \mr{Calcium \: chloride(aq)} + \\
                                                                                     &                   & \mr{Carbon \: dioxide(g)} + \mr{water(l)} \\
  \mr{Ordinary \: equation:} \; \; \ce{CaCO3} + \ce{2HCl}                        & \longrightarrow & \ce{CaCl2} + \ce{CO2} + \ce{H2O} \\
  \mr{Ionic \: equation:} \; \; \mr{CaCO3} + \mr{2H+} + \mr{2Cl-}    & \longrightarrow & \mr{2Cl}- + \mr{CO2} + \mr{H2O} \\
\eeqn

Here \ce{Cl} ions are spectator ions. Since the \ce{Ca} ions in Calcium
carbonate change from being in the solid state to being in aqueous
solution the formula of calcium carbonate is shown as a molecular
formula. Ionic equation omitting spectator ions:

\[ \ce{ CaCO3 + 2H+ {\longrightarrow} CO2 + H2O + Ca_{(aq)}^{2+} } \]

\subsubsection{Acids Reacting With Metals}

Hydrogen is given off when most dilute acids (Nitric acid is an
exception) react with metals. Heat is needed for the less reactive
metals and lead and copper are too unreactive to give this reaction at
all.

\beqn
\mr{General \:equation:} \; \; \mr{Metal} + \mr{Acid} & \longrightarrow & \mr{Salt} + \mr{Hydrogen} \\
\mr{Word \: equation:} \; \; \mr{Zinc(s)} + \mr{Sulphuric \: acid(aq)} & \longrightarrow & \mr{Zinc\: sulphate(aq)} + \mr{Hydrogen(g)} \\
\mr{Ordinary\: equation:} \; \; \ce{Zn} + \ce{H2SO4}   &\longrightarrow& \ce{ZnSO4} + \ce{H2} \\
\mr{Ionic\: equation:} \; \; \ce{Zn} + \ce{2H+} + \ce{SO4^{2-}}  &\longrightarrow& \ce{Zn^{2+}} + \ce{SO4^{2-}} + \ce{H2} \\
\eeqn

Here sulphate ions are spectator ions, so they can be omitted from the
final ionic equation. Ionic equation omitting spectator ions:

\[ \ce{ Zn + 2H- {\longrightarrow} Zn_{(aq)}^{2+} + H2{(g)} } \]

\section{Ammonia, Fertilisers, Equilibrium \& Sulphur}

\subsection{Nitrogen}

Nitrogen is a colourless, odourless gas which makes up about 78\% of
the composition of the air. It is a diatomic gas covalently bonded by
a triple covalent bond.

It is an extremely unreactive and many of its uses (e.g.\ Liquid
nitrogen for fast freezing food, Nitrates for fertiliser) depend on
its inertness. However, Nitrogen is essential for healthy life as it
is an important component of protein molecules.

Nitrogen is found in a variety of inorganic compounds either as
Ammonium compounds \ce{NH4+} or as Ammonia \ce{NH3}.

\subsection{Ammonia}

Ammonia is a weak base which produces an alkaline solution. It is
sometimes used in cleaning agents as a degreasing agent. It convert
grease into soluble soaps. This reaction is called Saponification.

Ammonia gas dissolves in water to form an aqueous solution called
Ammonium hydroxide:

\[ \ce{NH3} + \ce{H2O} \rightleftharpoons \ce{NH4+} + \ce{OH-} \]

Ammonia is in great demand throughout the world. It has a variety of
uses, as shown by the pie chart below.
\bigskip
\begin{center}
  \begin{tikzpicture}
    \draw (0,0) circle (4cm);
    \draw (0,0) -- (288:4cm);
    \draw (0,0) -- (324:4cm);
    \draw (0,0) -- (342:4cm);
    \draw (0,0) -- (360:4cm);
    \draw (0,0) (144:2cm) node {\parbox{4cm}{\center Fertilisers \\ 80\%}};
    \draw (0,0) (306:5cm) node {\parbox{3cm}{\center Wood pulp production 10\%}};
    \draw (0,0) (333:5cm) node {\parbox{3cm}{\center Nitric acid 5\%}};
    \draw (0,0) (351:5cm) node {\parbox{3cm}{\center Nylon 5\%}};
  \end{tikzpicture}
\end{center}
\bigskip
The manufacture of ammonia from nitrogen and hydrogen in the
laboratory is almost impossible.

\[ \ce{N2} + \ce{3H2} \rightleftharpoons \ce{2NH3} \]

In industry, as the conditions can be carefully controlled, it becomes
possible (this process is called the Haber Process after the German
chemist Fritz Haber).

\subsection{Chemical Equilibria}

How far do chemical reactions go?

When dry blue powdered copper (II) sulphate crystals are heated a
vapour is given off and a white residue remains. If the vapour is
condensed and collected it can be shown to be water. The white residue
is anhydrous Copper(II) sulphate.

\[ \ce{ CuSO4 + 5H2O {\xrightarrow{forwards\: reaction}} CuSO4 + 5H2O \;\;\;\; endothermic\:({{\Delta}\mr{H}+}) } \]

When a few drops of water are added to the cold anhydrous Copper(II)
sulphate the crystals turn blue and heat energy is recovered.

\[ \ce{ CuSO4 + 5H2O {\xrightarrow{backwards\: reaction}} CuSO4 + 5H2O \;\;\;\; exothermic\:({{\Delta}\mr{H}-}) } \]

This type of reaction is an example of a reversible reaction. A
reversible change is one in which the products formed are capable of
reacting with each other to reform the original substance or
substances.

Reactions that can proceed in both directions are given a
$\rightleftharpoons$ sign between the reactants and products.

The special kind of balance which keeps still by moving is called an
\textbf{Equilibrium}.

Chemical equilibria are very common in industrial processes where
gases are involved because the reactions take place within a closed
system. Factors which affect the rate of a chemical reaction might
effect the position of an equilibrium reaction as there are two
opposing rates to consider. Reaction conditions must be carefully
chosen so that the process is economically viable.

Some chemical reactions are reversible, in that not only can reactants
form products, but also products can form reactants, e.g.\ heated iron
reacts with steam to form iron oxide and hydrogen, while heated iron
oxide reacts with hydrogen to form iron and steam.

For a particular reaction, it is possible for reactants and products
to be present in a \textbf{dynamic equilibrium} with one another. This
means that the amounts of reactants and products remain constant, due
to the rate at which reactants form products exactly equalling the
rate at which products form reactants.

The position of an equilibrium (i.e.\ the relative amounts of
reactants and products present at equilibrium --- effectively the
yield of products) can be affected by changes in the reaction
conditions. Changes can be predicted using \textbf{Le Chatelier's
  Principle}. This states that:

\begin{quote}
  \textit{Whenever a system in dynamic equilibrium is disturbed, it
    tends to respond in such a way as to oppose the disturbance and so
    restore equilibrium.}
\end{quote}

\subsubsection{Le Chatelier's Principle}

\paragraph{Concentration}

if the concentration of a reactant or product is altered when a
chemical system is in equilibrium the equilibrium will try to restore
it. So if a product is removed as the equilibrium proceeds then the
equilibrium will try to increase the products' concentration and so
increase the yield.

\paragraph{Temperature}

Most reactions give out heat when the reactants react to form the
products, i.e.\ the formation of products is exothermic. This means
that the formation of reactants from products is endothermic --- it
absorbs heat. If a reaction of this sort is in equilibrium, and an
increase in termperature is applied, the position of equilibrium will
move in an attempt to lower the temperature. This means that more
reactants will be formed, as this will absorb heat. Therefore the
yield of products is reduced by an increase in temperature.

\paragraph{Pressure} (\emph{\small For reactions involving gases})

If, for example, there are less gas molecules on the products side of
the equation than on the reactants side, then a movement to form more
products will produce a decrease in pressure. This, if the pressure is
increased on a reaction of this sort in equilibium, then the posiion
of equilibrium will move in an attempt to lower the
pressure. Therefore more products will be formed and the yield of
products is increased by an increase in pressure.

% Two important industrial processes which involve reversible
% reactions which can reach dynamic equilibrium are now
% described. ---- Where should this go?

\subsection{Manufacture of Ammonia --- The Haber Process}

The Haber Process is the syntheses of Ammonia (\ce{NH3}) from Nitrogen and Hydrogen.

\[ \ce{Nitrogen + Hydrogen {\rightleftharpoons} Ammonia} \]

\[ \ce{N2{(g)} + 3H2{(g)} {\rightleftharpoons} 2NH3{(g)}} \]

The production of Ammonia is exothermic and there are less gas
molecules on the products side of the equation than on the reactants
side. Therefore, a high yield of Ammonia is favoured by a low
temperature and a high pressure.

Conditions used to obtain a satisfactory yield at a satisfactory rate:

\begin{description}
\item[Moderate temperature (450$\ensuremath{^\circ}$C)] Higher
  temperature favours the decomposition of Ammonia, thereby reducing
  the yield. Lower temperature reduces the rate of reaction.
\item[Moderate pressure (200 atmospheres)] Higher pressure increases
  cost of industrial plant, lower pressure decreases both yield and
  rate.
\item[Catalyst (iron)] Helps to produce a satisfactory rate, but does
  not change the equilibrium yield, as it speeds up the production of
  ammonia and the decomposition of Ammonia equally.
\end{description}

\input{haber.pic}

\subsection{Manufacture of Nitric Acid}

One of the main uses of Ammonia is to convert it into Nitric acid.

The Nitrogen dioxide is formed in a two step process. First the
Ammonia is oxidised by air in the presence of a Platinum catalyst to
produce Nitrogen monoxide.

\[ \ce{4NH3 + 5O2 {\rightleftharpoons} 4NO + 6H2O} \]

This reaction is exothermic.

As the mixture cools the Nitrogen monoxide reacts with more air to
give Nitrogen dioxide.

\[ \ce{6NO + 3O2 + 2H2O {\rightleftharpoons} 4HNO3 + 2NO} \]

\[ \ce{2NO + O2 {\rightleftharpoons} 2NO2} \]

\[ \ce{2MO2 + H2O {\rightleftharpoons} 2HNO3} \]

On reaction with water Nitric acid is formed.

Apart from fertilisers Nitric acis is also used to make explosives. An
Italian chemist called Professr Sobrero converted Nitric acid into
Nitroglycerine, a very unstable oily liquid. It was Alfred Nobel who
lost his borther in a Nitroglycerine explosion who was responsible for
stabilising it by mixing it with clay to form Dynamite.

\subsection{Manufacture of Sulphuric Acid --- The Contact Process}

Sulphuric acid is manufactured from sulphur in the following stages:

\begin{enumerate}
\item Sulphur is burned in air to make Sulphur dioxide (\ce{SO2})
\item
  \beqn
    \ce{Sulphur\: dioxide + Oxygen} & \rightleftharpoons & \ce{Sulphur\: trioxide} \\
    \ce{2SO2{(g)} + O2{(g)}} & \rightleftharpoons &
    \ce{2SO3{(g)}}
  \eeqn
  The production of Sulphur trioxide in this stage is exothermic and
  there are less gas molecules on the products side of the equation
  than on the reactants side. Therefore a high yield of Sulphur
  trioxide is favoured by a low temperature and a high pressure.  In
  practice, to obtain a satisfactory yield at a satisfactory rate, the
  following conditions are used:
  \begin{description}
  \item[Temperature of 450$^\circ$C] This is a compromise
    termperature, as a lower temperature would decrease the rate of
    reaction and a higher temperature would decrease the yield.
  \item[Pressure only just above atmospheric] Rate and yield are
    satisfactory wwithout the need for high pressure.
  \item[Catalyst of Vanadium pentoxide (\ce{V2O5})] This increases the
    rate of reaction (but has no effect on yield)
  \end{description}
\item The Sulphur trioxide is absorbed in concentrated Sulphuric acid
  and the resulting liquid is added to water.
\end{enumerate}

The Sulphur dioxide needed is obtained from:
\begin{itemize}
\item The combustion of Sulphur
\item The removal of unpleasant-smelling Sulphur compounds from
  petroleum oil
\item The removal of Hydrogen sulphide from natural gas (not North Sea
  gas)
\item Roasting metal sulphides in order to extract metals from their
  ores
\end{itemize}

\input{contact.pic}

Sulphur dioxide and air are purified by electrostatic precipitation.

A Sulphuric acid plant must be sited in a place where supplies of
Sulphur dioxide can reach it, that is, near a port where caroes of
Sulphur can arrive by ship, or near a gas refinery or a metal smelter.

\bigskip
\begin{center}
  \begin{tikzpicture}
    \coordinate (O) at (0,0);
    \draw (O) circle (6cm);
    \coordinate (A) at (360 * 2 / 7:6cm);
    \coordinate (B) at (360 * 2 / 7 + 360 * 1 / 7:6cm);
    \coordinate (C) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7:6cm);
    \coordinate (D) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7:6cm);
    \coordinate (E) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7:6cm);
    \coordinate (F) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 14:6cm);
    \coordinate (G) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 14 + 360 * 1 / 42:6cm);
    \coordinate (H) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 14 + 360 * 1 / 42 + 360 * 1 / 42:6cm);
    \coordinate (I) at (360 * 2 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 7 + 360 * 1 / 14 + 360 * 1 / 42 + 360 * 1 / 42 + 360 * 1 / 42:6cm);
    \draw (O)--(A) node [shift={(4cm,-3cm)}] {\parbox{3cm}{\center Fertilisers: \\ phosphates and ammonium sulphate}} ;
    \draw (O)--(B) node [shift={(2.5cm,1cm)}] {\parbox{3cm}{\center Soaps and detergents}} ;
    \draw (O)--(C) node [shift={(1.75cm,2.75cm)}] {\parbox{3cm}{\center Soaps Paints and pigments, e.g.\ \ce{TiO2}}} ;
    \draw (O)--(D) node [shift={(-1.25cm,3.25cm)}] {\parbox{4cm}{\center Batteries \\ Pharmaceuticals \\ Insecticides}} ;
    \draw (O)--(E) node [shift={(-2.75cm,0.75cm)}] {\parbox{4cm}{\center Plastics and many chemicals, including metal sulphates}} ;
    \draw (O)--(F) node [shift={(-2cm,0cm)}] {\parbox{2cm}{\center Fibres, e.g.\ nylon}} ;
    \draw (O)--(G); \coordinate (Gpoint) at ($(G) - (0.5,0.25)$); \node at ($(Gpoint) + (1.5,-0.5)$) (Glabel) {Dyes}; \draw[->] (Glabel) -- (Gpoint);
    \draw (O)--(H); \coordinate (Hpoint) at ($(H) - (0.25,0.25)$); \node at ($(Hpoint) + (2.5,-0.5)$) (Hlabel) {Oil and petrol}; \draw[->] (Hlabel) -- (Hpoint);
    \draw (O)--(I); \coordinate (Ipoint) at ($(I) - (0.25,0.5)$); \node at ($(Ipoint) + (2.5,0.5)$) (Ilabel) {\parbox{2cm}{\center Pickling iron and steel}}; \draw[->] (Ilabel) -- (Ipoint);
  \end{tikzpicture}
\end{center}
\bigskip

\subsection{How The Chemical Industry Is Organised}

All manufactueres -- whether of chemical products of anything else --
are engaged in a process which may be summed up as:

\[ \mr{raw \: materials} \rightarrow \mr{processing} \rightarrow \mr{products} \]

which means taht they are concerned with:

\[ \mr{supplies} \rightarrow \mr{manufacture} \rightarrow \mr{sales} \]

The chemical industry is a business which has grown up to provide a
livelihood for those who work in it, and a profit for shareholders who
have invested money in chemical companies. At the same time it is
there to meet the need for an ever-growing range of materials and
products.

\subsubsection{Processing \& Manufacture}

The major divisions of chemical industry are:

\begin{tabular}{ll} \hline
agricultural chemicals & heavy chemicals \\
dyestuffs & metals \\
explosives & paints \\
fibres & plastics \& petrochemicals \\
fien chemicals & pharmaceuticals \\ \hline
\end{tabular}

\subsubsection{Locating a Chemical Plant}

The decision on where to build a particular chemcial plant is an
extremely complicated one. These are some of the more important things
whcih have to be thought about:

\begin{description}
\item[Communications] road, rail, sea and air access are neede for
  bringing in raw materials and distributing products.
\item[Environment] this must not me affected too much while building
  the plant, or disposing of its waste.
\item[Power supply] this must be available, or it must be possible to
  generate power at the site.
\item[Utilities] examples are water and fuel; these must be available
  at reasonable cost.
\item[Workers] these must be recruited, and perhaps moved to the area
  and housed.
\end{description}

\subsubsection{The Supply of Raw Materials}

The main raw metrials for the chemical industry are: oil and natural
gas, coal, metal ores, minerals like salt and limstone, and the gases
of the air. All of these must be round, extracted and transported to
where they are needed. There are important issues here:

\begin{itemize}
\item Some raw materials are running out. Since new mineral deposits
  are beign found all the time, and enw methods for exploiting them
  are beign developed, it is not possible to say precisely how long
  any particular materials will last. Our own supplies of fossil fuels
  are a good example. Coal will last longer than the others, if
  wecontinue extraction at the present rate. The chemical industry is
  already adapting to likely changes in its supply of raw materials.
\item Our supply of some materials, notably tin, mercury, uranium and
  gold, depends on the fact that miners in some parts of the world
  work in dangerous conditions for low rates of pay. So long as the
  world wants these materials, someone has to get them out. Social and
  political changes in different parts of the world may have a
  considerable effect on the prices and supply of some metal ores.
\end{itemize}

\subsection{The Manufacture \& Use of Fertilisers}

Ammonia and sulphuric acid are both used in the manufacture of
fertiliesrs. Aqueous ammonia can be used directly as a nitrogenous
fertiliser. Ammonia can also be used to manufacture nitric acid and
ammonium salts, e.g.\ ammonium nitrate \ce{PNH4NO3}, is manufactured
by the reaction of ammonia and nitric acid.

Ammonium salts (e.g.\ ammonium nitrate), minerals and some phosphates
are soluble in water, and if these are washed into lakes and rivers
they cause excessive plant growth. The decay of this plant material
deoxygenates the water. Nitrates are very difficult to remvoe from
domestic water sources, and are potentially harmful to health.

The main elements required for healthy plant growth are:

\begin{description}
\item[Nitrogen] taken into plant roots in the form of nitrate ions; a
  lack causes stunted growth, harsh and fibrous leaves
\item[Phosphorus] a lack causes stunted growth, and stunted grey
  leaves
\item[Potassium] a lack causes stunted growth, and premature death of
  leaves
\end{description}

NPK fertiliers must contain the appropriate compositions of tehse
elements. In addition, physical state, solubility and pH are other
factors which must be considered when choosing a fertiliser.

\begin{table}
  \begin{tabular}{lll} \hline
    \it Raw material & Where it comes from & Used to make \\ \hline
    \rm nitrogen & the air & ammonia for all fertilisers \\
    water & reservoirs & ammonia \\
    natural gas & under the sea & ammonia \\
    potassium chloride & mines & compound fertilisers \\
    phosphate rock & mined & compound fertilisers \\
    sulphur & mined & compound fertilisers \\
  \end{tabular}
  \caption{Raw materials for the manufacture of fertilisers.}
\end{table}

\begin{figure}
  \begin{tikzpicture}
    \node (water) {water};
  \end{tikzpicture}
\end{figure}

\subsubsection{Problems with Fertilisers}

\section{Volumetric Analysis}

Many chemical reactions take place in aqueous solution and so it is
important to have a standard amount in solution.

Concentration is measured in $\frac{\mr{mol}}{\mr{dm}^3}$.

A 1 molar solution contains 1 mole of solute dissolved in exactly
1$dm^3$ of solvent, usually water.

So a 1 molar solution of Sodium chloride contains 58.5g of Sodium
chloride dissolved in 1000cm$^3$ of water.

\subsection{The Volumes \& Concentrations of Solutions}

The concentration can be stated in two ways:

\begin{enumerate}
\item In $\frac{\mr{mol}}{\mr{dm}^3}$, the amount, in moles,
  of solute contained in 1 dm$^3$ of solution.
\item In $\frac{\mr{g}}{\mr{dm}^3}$, the amount, in g, of
  solute contained in 1 dm$^3$ of solution.
\end{enumerate}

There then exists two similar simple relationships between the
concentration of a solution, amount of solute and the volume of the
solution:

\begin{enumerate}
\item $\mr{Concentration}\: (\frac{\mr{mol}}{\mr{dm}^3}) = \frac{\mr{amount}}{\mr{volume}}$
\item $\mr{Concentration}\: (\frac{\mr{g}}{\mr{dm}^3}) = \frac{\mr{mass}}{\mr{volume}}$
\end{enumerate}

These can be combined to form:

\[ \mr{Concentration}\: (\frac{\mr{g}}{\mr{dm}^3}) = \mr{Concentration}\: (\frac{\mr{mol}}{\mr{dm}^3}) \times \mr{Molar\: mass} (\frac{\mr{g}}{\mr{mol}}) \]

\subsection{Titrations}

\subsubsection{Mathod}

\subsubsection{Calculation}

\subsection{Volumetric Analysis}

\subsubsection{The Pipette}

\subsubsection{The Burette}

\subsubsection{Performing a Titration}

\section{Organic I}


Organic Chemistry is the study of the chemistry of the element
Carbon. Carbon has the unique ability to bond to both itself and many
other elements (mainly non-metallic). The main sources of Carbon are
plants, animals, coal, crude oil and natural gas. Today fossil fuels
provide 93\% of our fuels while nuclear and hydoelectric power only
provide 7\%.

\begin{tabular}{lclllll}
		 & $\nearrow$    & Coal 34\%        & $\rightarrow$ & (heat without \ce{O2}) & $\rightarrow$ & Coal gas \\
Fossil fuels are & $\rightarrow$ & Crude oil 34\%   &               & $\downarrow$           & $\searrow$    & \\
		 & $\searrow$    & Natural gas 24\% &               & Coke                   &               & Coal tar
\end{tabular}

\subsection{Fuels}

Natural gas is 97\% Methane.

Petrol is a mixture of Hydrocarbons.

\subsubsection{Fractional Distillation}

\begin{tabular}{crll}
  \multirow{6}{*}{$\downarrow$} & 1 & Petroleum gas & \\
  & 2 & Petroleum fraction & -- petrol engines, cars (gasoline) \\
  & 3 & Paraffin & -- oil stoves, aircraft fuel (kerosene) \\
  & 4 & Diesel & -- diesel engines \\
  & 5 & Lubrication fraction & -- lubricants, waxes \& polishes \\
  & 6 & Bitumen fraction & -- roads
\end{tabular}

\medskip

(\emph{higher boiling point/heavier/larger molecules towards bottom})

Carbon dioxide is produced by:

\begin{itemize}
\item complete combustion (e.g.\ hydrocarbons)
\item respiraton
\item reaction of acids \& alkalis
\end{itemize}

\subsection{Naming Organic Compounds}

\begin{table}[!htbp]
  \centering
  \begin{tabular}{lr}
    \hline
    Name    & No.\ of Carbon Atoms \\ \hline
    Methane & 1 \\
    Ethane  & 2 \\
    Propane & 3 \\
    Butane  & 4 \\
    Pentane & 5 \\
    Hexane  & 6 \\ \hline
  \end{tabular}
  \caption{Names \& numbers of carbon atoms in alkanes.}
\end{table}

\begin{table}[!htbp]
  \centering
  \begin{tabular}{ll}
    \hline
    Side Chains (\emph{allyl}) & Formula     \\ \hline
    methyl                     & \ce{CH3}--  \\
    ethyl                      & \ce{C2H5}-- \\
    propyl                     & \ce{C3H7}-- \\ \hline
  \end{tabular}
  \caption{Formulae of allyls.}
\end{table}

\[
\begin{array}{ccccccccc}
  &&&& \ce{CH3} &&&& \\
  1 && 2 && \textSFxi 3 && 4 && 5 \\
  \ce{CH3} & --- & \ce{CH} & --- & \ce{CH} & --- & \ce{CH2} & --- & \ce{CH3} \\
  && \textSFxi &&&&&& \\
  && \ce{CH3} && \multicolumn{4}{c}{2,3-diMethylpentane}
\end{array}
\]

\subsection{Homologous Series}

A homologous series is a group of similar molecules. For example:

\begin{itemize}
\item Alkanes
\item Alkenes
\item Carbolic acid (with \ce{CO2H} group)
\item Aldehydes
\item Alcohols (with \ce{OH} group)
\end{itemize}

Structural isomerism is where two molecules have the same molecular
formula, but have different structual formulae.

\subsection{Alkenes}

General formula is \ce{C_nH_{2n}}.

\begin{itemize}
\item Contain a \ce{C\,=\,C} double covalent bond
\item Are unsaturated hydrocarbons
\item Need at least 2 Carbon atoms
\end{itemize}

\begin{itemize}
\item Ethene -- \ce{C2H4} \\
\includegraphics{ethene}
\item Propene -- \ce{C3H6} \\
\includegraphics{propene}
\item Butene -- \ce{C3H8} \\
\begin{itemize}
\item but-1-ene -- \ce{CH3CH2CH\,=\,CH2}
\item but-2-ene (two isomers) -- \ce{CH3CH\,=\,CHCH3}\\
\end{itemize}
\end{itemize}

\includegraphics{but-2-ene-1} \hskip 2cm \emph{and} \hskip 2cm \includegraphics{but-2-ene-2}

\begin{figure}[!h]
\centering
\begin{framed}
\includegraphics{additionreaction}
\end{framed}
\caption{Alkenes undergo addition reactions (regardless of light conditions)}
\end{figure}

The test to determine whether is substance is an Alkane or Alkene
(i.e.\ a test for unsaturation) is to add Bromine water.

\subsection{Alkanes}

Alkanes undergo a substitution reacction with Halogens in the presence
of light.

\subsection{Reactions of Alkanes \& Alkenes}

\subsubsection{Addition Reactions}

\subsection{Polymers}

\subsubsection{Synthetic Organic Polymers}

\begin{figure}[!h]
  \centering
  \begin{framed}
    \includegraphics{cyclohexanereaction}
  \end{framed}
  \caption{Addition reaction of Cyclohexane and Bromine}
\end{figure}

\subsubsection{Polymerisation}

\section{Rates of Reaction}

Different chemical reactions take place at different speeds. Some
reactions seem instantaneous on mixing the reactants, e.g. \\ Silver
nitrate solution \& \\ Sodium chloride.

As soon as these two reactants are mixed a white precipitate is
formed.

Some reactions require energy ebfore they start, e.g.\ the burning of
a piece of Magnesium. Some reactions take a long time, e.g.\ the
rusting of Iron.

\[ \ce{Reactants {\longrightarrow} Products} \]

You can measure the reate of appearance of a product or the rate of
disappearance of a reactant.

So you need to measure a property of the product/reactant that changes
with time:

\begin{itemize}
\item Mass
\item Volume
\item Colour
\end{itemize}

\subsubsection*{Methods of measuring rates of reactions}

(\emph{for reactions which involve the production of a gas})

\begin{itemize}
\item Measure the volume of the gas product at fixed time intervals.
\item If \ce{CO2}: measure the loss in mass of the reaction mixture.
\end{itemize}

\subsubsection*{Factors which affect the rate of reaction}

\begin{itemize}
\item Concentration
\item Temperature
\item Surface Area
\item Presence of a catalyst (can be organic or inorganic)
\end{itemize}

\begin{framed}
  \textbf{\large Note:} In order for a chemical reaction to take
  place, the particles must collide with sifficient force. Not all
  collisions produce a reaction --- the collision must have the right
  properties (force, type \&c.) \end{framed}

\subsection{The Collision Theory}

To understand why different reactions proceed at different rates, and
why the rates are affected by concentration and other factors, we have
to consider reactions at a mmolecular level.

It is obvious that if two particles (atoms, molecules of ions) are to
react they have to collide with each other, although, at ordinary room
temperatures, only a very small proportion of molecular collisions
result in reaction.

The rate of a reaction will be increased by any change which makes the
reactant particles collide more frequently, or which makes a greater
proportion of collisions result in reaction.

%Factors 1. - 4. will now be discussed ---- where does this go?

\subsection{Concentration}

The greater the concentration of any reactant (i.e.\ teh more
particles per unit volume), the greater will be the number of
collisions per second -- therefore the faster will be the reaction.

For a gaseous reaction, an increase in pressure produces a decrease in
volume and an increase in concentration. Therefore an increase in
pressure makes a gaseous reaction faster.

\subsection{`Lump' Size}

For reactions involving solids, the smaller the `lump' size the faster
the reaction --- this is because the smaller the `lump' size the
greater the total surface area where the reactant particles can come
into contact with each other.

\subsection{Temperature}

All chemical reactions are speeded up by an increase in temperature. A
temperature rise means that the particles move faster. If they move
faster then:

\begin{itemize}
\item They collide more often
\item On average, the collisions are more energetic --- so that
  collisions are more likely to result in reaction (i.e.\ a greater
  proportion of all collisions result in reaction).
\end{itemize}

A temperature rise thus increases reaction rates in two ways, of which
the second is the more effective.

\subsection{Catalysts}

A catalyst may be defined as a substance which alters (generally
increases) the rate of a chemical reaction without itself being used
up.

\begin{itemize}
\item \textbf{Chemical catalysts} --- These function in two ways:
  \begin{itemize}
  \item All catalysts change the `route' of reaction to one which
    requites less energy to `activate' it. The new route is therefore
    a faster one.
  \item Some catalysts also act by bringing together the reacting
    aprticles on to the surface of the catalyst, therefore increasing
    the reactant concentrations and the rate of reaction.
  \end{itemize}
  Examples of catalysts:
  \begin{itemize}
    \item Manganese(IV) oxide in the decomposition of Hydrogen peroxide into Oxygen and water.
    \item Iron in the manufacture (synthesis) of Ammonia (\ce{NH3}) from Nitrogen and Hydrogen --- the Haber Process
    \item Vanadium(V) oxide in the manufacture of Sulphuric acid, via Sulphur trioxide, from Sulphur dioxide and Oxygen --- the Contact Process
  \end{itemize}
\item \textbf{Enzymes}
  \begin{itemize}
  \item Enzymes are biological catalysts and they speed up the
    chemical reactions which go on in living things
  \item They are always proteins
  \item They are specific in their action, in that each enzyme
    controls one particular reaction, or type of reaction
  \item They are destroyed by heat, this process being called
    \textbf{denaturation}
  \item Therefore they stop functioning above about 45$^\circ$C,
    working best over a limited range of temperature (35--40$^\circ$C
    approx.)
  \item When a reactant (\textbf{substrate}) molecule collides with a
    molecule of the correct enzyme, it can fit into a depression on
    the surface of the enzyme molecule, called the \textbf{active
      site}. The reaction then takes place and the molecules of
    product leave the active site, freeing it for another substrate
    molecule.
  \item The active site of a particular enzyme has a specific shape
    into which only one kind of substrate will fit. This is why
    enzymes are specific in their action.
  \end{itemize}
  Examples of enzymes:
  \begin{itemize}
  \item Catalase, present, e.g.\ in the liver, catalyses the
    decomposition of Hydrogen peroxide into Oxygen and water. This
    process is vital, as Hydrogen peroxide is poisonous (and is
    closely involved in the process of ageing)
  \item Zymase, present in yeast, catalyses the fermentation of
    glucose into alcohol (ethanol)
  \item Various protein-digesting enzymes (proteases), present in
    biological washing powders, remove protein stains, such as gravy,
    from clothes
  \end{itemize}

\end{itemize}

\section{Enthalpy}

\subsection{Enthalpy Changes ($\Delta H$)}

\subsection{Calculations Using Bond Energies}

\section{Organic II}

\subsection{Naming Organic Compounds}

\subsection{Manufacture of Ethanol}

\subsection{Esters}

\subsection{Carboxylic Acids}

\section{Electro-Chemistry}

\subsection{Electrolysis}

%\subsubsection{General Principle of Electrolysis} --- is this header really necessary?

\begin{itemize}
\item At the cathode (negative), metal or hydrogen is
  produced. \begin{itemize}
  \item Hydrogen is produced if the metal is \ce{Al} or higher. Metal
    is produced if it is \ce{Zn} or lower (all on the reactivity
    series). \end{itemize}
\item At the anode (positive), non-metals (apart from Hydrogen) are
  formed.
  \begin{itemize}
  \item \ce{F2}, \ce{Cl2}, \ce{Br2}\ \ce{I2} are formed in preference
    to oxygen, unless the solution is dilute, in which case oxygen is
    formed from \ce{OH-} ions, according to the formula:
    \[ \ce{4OH-} \longrightarrow \ce{2H2O} + \ce{O2} + \ce{4e-} \]
  \item Nitrates and Sulphates do not decompose and Oxygen will be
    formed at the anode instead
  \end{itemize}
\item Anything above Zinc in the reactivity series must be extracted
  from its natural ore using electrolysis. Zinc and below can be
  extracted by heating with Carbon.
\item Electrolyte -- a substance that conducts electricity when
  dissolved in water or molten.
\end{itemize}

\subsubsection{Reactivity Series}

\begin{table}[htb!]
  \centering
  \begin{tabular}{llc}
    Element                    & Mnemonic & Reactivity    \\ \hline
    Potassium                  & Police   & \textsc{high} \\
    Sodium                     & Seargent & $\uparrow$    \\
    Calcium                    & Charlie  &               \\
    Lithium                    &          &               \\
    Beryllium                  &          &               \\
    Magnesium                  & M--      &               \\
    Aluminium                  & A--      &               \\
    $\uparrow$ \ce{H2} formed  &          &               \\
    (Carbon)                   &          &               \\
    $\downarrow$ metal formed  &          &               \\
    Zinc                       & Z--      &               \\
    Iron                       & I--      &               \\
    (Hydrogen in Electrolysis) &          &               \\
    Nickel                     & N--      &               \\
    Tin                        & T--      &               \\
    Lead                       & L--      &               \\
    Hydrogen                   & Has      &               \\
    Copper                     & Caught   &               \\
    Mercury                    & Me       &               \\
    Silver                     & Stealing &               \\
    Gold                       & Gold     & $\downarrow$  \\
    Platinum                   & Plates   & \textsc{low}  \\ \hline
  \end{tabular} \linebreak \\[4pt]
  \parbox{0.75\textwidth}{\small More reactive elements prefer to \emph{stay} as ions when in solution, and are more likely to be formed at the cathode.
    In the reaction:
    \ce{X_{(s)} + Y+_{(aq)}}
    Where \ce{X} is \emph{more} reactive than \ce{Y}, the result will be:
    \ce{X+_{(aq)} + Y_{(s)}}
    (the charges could be $2+$, $3+$ \&c.)}
  \caption{Table of the Reactivity Series}
\end{table}

\begin{table}[htb!]
  \centering
  \begin{tabular}{lc}
    Element/Oxide ion  & Reactivity    \\ \hline
    \ce{I2}            & \textsc{high} \\
    \ce{Br2}           & $\uparrow$    \\
    \ce{Cl2}           &               \\
    \ce{F2}            & $\downarrow$  \\
    \ce{O2}            & \textsc{low}  \\
    \ce{NO3}           & Never formed  \\
    \ce{SO4}           & Never formed  \\ \hline
  \end{tabular} \linebreak \\[4pt]
  \parbox{0.75\textwidth}{\small This assumes a concentrated solution; if dilute, it is more likely that simply Oxygen will be formed.}
  \caption{Non-Metal Reactivity Series}
\end{table}

\subsubsection{Metals}

Metals are stable in a lattics structure where all their electrons are
floating around freely (incidentally, this allows electrical
conductivity).

They are \emph{also} stable when they have a completely full/empty out
electron shell. This makes them ions.

So metals are found in nature either as ions or in in the lattice (sea
of electrons) structure.

(Carbon doesn't normally form ions --- it forms covalent bonds.)

\begin{sidewaystable}
  \thispagestyle{empty} \centering \scalebox{0.9}{
    \begin{tabular}{|rl||l|l|l|l|l|l|l|l|l|l|}
      \hline
      Name of Ion  & $\longrightarrow$ & Fluoride  & Chlorine   & Hydroxide    & Bromide    & Oxide        & Sulphide     & Sulphate       & Nitrate       & Carbonate      & Phosphate      \\
      $\downarrow$ & Symbol of ion     & \ce{F-}   & \ce{Cl-}   & \ce{OH-}     & \ce{Br-}   & \ce{O^{2-}}  & \ce{S^{2-}}  & \ce{SO4^{2-}}  & \ce{NO^{3-}}  & \ce{CO3^{2-}}  & \ce{PO4^{3-}}  \\ \hline \hline
      Hydrogen     & \ce{H+}           & \ce{HF}   & \ce{HCl}   & \ce{H2O}     & \ce{HBr}   & \ce{H2O}     & \ce{H2S}     & \ce{H2SO4}     & \ce{HNO3}     & \ce{H2CO3}     & \ce{H3PO4}     \\ \hline
      Sodium       & \ce{Na+}          & \ce{NaF}  & \ce{NaCl}  & \ce{NaOH}    & \ce{NaBr}  & \ce{Na2O}    & \ce{Na2S}    & \ce{Na2SO4}    & \ce{NaNO3}    & \ce{Na2CO3}    & \ce{Na3PO4}    \\ \hline
      Potassium    & \ce{K+}           & \ce{KF}   & \ce{Kcl}   & \ce{KOH}     & \ce{KBr}   & \ce{K2O}     & \ce{K2S}     & \ce{K2SO4}     & \ce{KNO3}     & \ce{ K2CO3}    & \ce{K3PO4}     \\ \hline
      Lithium      & \ce{Li+}          & \ce{LiF}  & \ce{LiCl}  & \ce{LiOH}    & \ce{LiBr}  & \ce{Li2O}    & \ce{Li2S}    & \ce{Li2SO4}    & \ce{LiNO3}    & \ce{Li2CO3}    & \ce{Li3PO4}    \\ \hline
      Ammonium     & \ce{NH4+}         & \ce{NH4F} & \ce{NH4Cl} & \ce{NH4OH}   & \ce{NH4Br} & \ce{(NH4)2O} & \ce{(NH4)2S} & \ce{(NH4)2SO4} & \ce{NH4NO3}   & \ce{(NH4)2CO3} & \ce{(NH4)3PO4} \\ \hline
      Zinc         & \ce{Zn^{2+}}      & \ce{ZnF2} & \ce{ZnCl2} & \ce{Zn(OH)2} & \ce{ZnBr2} & \ce{ZnO}     & \ce{ZnS}     & \ce{ZnSO4}     & \ce{Zn(NO3)2} & \ce{ZnCO3}     & \ce{Zn3(PO4)2} \\ \hline
      Lead         & \ce{Pb^{2+}}      & \ce{PbF2} & \ce{PbCl2} & \ce{Pb(OH)2} & \ce{PbBr2} & \ce{PbO}     & \ce{PbS}     & \ce{PbSO4}     & \ce{Pb(No3)2} & \ce{PbCO3}     & \ce{Pb3(PO4)2} \\ \hline
      Magnesium    & \ce{Mg^{2+}}      & \ce{MgF2} & \ce{MgCl2} & \ce{Mg(OH)2} & \ce{MgBr2} & \ce{MgO}     & \ce{MgS}     & \ce{MgSO4}     & \ce{Mg(No3)2} & \ce{MgCO3}     & \ce{Mg3(PO4)2} \\ \hline
      Calcium      & \ce{Ca^{2+}}      & \ce{CaF2} & \ce{CaCl2} & \ce{Ca(OH)2} & \ce{CaBr2} & \ce{CaO}     & \ce{CaS}     & \ce{CaSO4}     & \ce{Ca(No3)2} & \ce{CaCO3}     & \ce{Ca3(PO4)2} \\ \hline
      Copper (II)  & \ce{Cu^{2+}}      & \ce{CuF2} & \ce{CuCl2} & \ce{Cu(OH)2} & \ce{CuBr2} & \ce{CuO}     & \ce{CuS}     & \ce{CuSO4}     & \ce{Cu(No3)2} & \ce{CuCO3}     & \ce{Cu3(PO4)2} \\ \hline
      Iron (III)   & \ce{Fe^{3+}}      & \ce{FeF3} & \ce{FeCl3} & \ce{Fe(OH)3} & \ce{FeBr3} & \ce{Fe2O3}   & \ce{Fe2S3}   & \ce{Fe2(SO4)3} & \ce{Fe(NO3)3} & \ce{Fe2(CO3)3} & \ce{FePO4}     \\ \hline
      Aluminium    & \ce{Al^{3+}}      & \ce{AlF3} & \ce{AlCl3} & \ce{Al(OH)3} & \ce{AlBr3} & \ce{Al2O3}   & \ce{Al2S3}   & \ce{Al2(SO4)3} & \ce{Al(NO3)3} & \ce{Al2(CO3)3} & \ce{AlPO4}     \\ \hline
    \end{tabular}}
  \caption{Table of Ions \& Ionic Compounds}
\end{sidewaystable}

\subsubsection{Molten Ionic Compounds}

\subsubsection{Aqueous Solutions}

\paragraph{Inert Electrodes}

\paragraph{Metal Electrodes}

\subsection{Producing Electricity From Chemical Reactions}

\subsubsection{Diagram of Simple Cell}

\begin{table}
\begin{tabular}{lp{6cm}p{5cm}}\hline
\it anion & \it test & \it test result \\ \hline
carbonate (\ce{CO3^{2-}}) & add dilute acid & effervescence, carbon dioxide produced \\
aqueous chloride (\ce{Cl-}) & acidify with dilute nitric acid, then add aqueous silver nitrate & white precipitate \\
aqueous iodide (\ce{I-}) & acidify with dilute nitric acid, then add aqueous silver nitrate & yellow precipitate \\
aqueous nitrate (\ce{NO3^-}) & add aqueous sodium hydroxide, then aluminium foil; warm carefully & ammonia produced \\
aqueous sulphate (\ce{SO4^{2-}}) & acidify, then add aqueous barium nitrate & white precipitate \\ \hline
\end{tabular}
\caption{Tests for anions.}
\end{table}

\end{document}

