State the name of the aluminium compound found in bauxite.
Name the substance in which purified bauxite is dissolved before electrolysis takes place.
Name the substance used for the positive electrodes.
Write the ionic half-equation for the production of aluminium at the negative electrode.
Explain why a reaction is not seen immediately.
Complete the ionic equation for this reaction. $\ldots\mathrm{Al}+\ldots\mathrm{Zn}^{2+}\rightarrow\ldots\mathrm{Al}^{3+}+\ldots\mathrm{Zn}$
State the oxidation number of zinc in: $\mathrm{Zn}^{2+}$ ; $\mathrm{Zn}$.
Define the term reduction in terms of oxidation number.
State what the symbol $\Delta H$ means.
State what can be deduced from the negative sign in $\Delta H=-850\text{ kJ/mol}$.
State what is meant by the term amphoteric.
Write a symbol equation for this reaction.
Deduce the formula of: gallium(III) bromide; gallium(III) sulfate.