Translate the following into the language of chemistry: 

Sulphur dioxide reacts with oxygen at $450°\mathrm{C}$in the presence of a catalyst $\left({\mathrm{V}}_2{\mathrm{O}}_5\right)$to form sulphur trioxide. The reaction is reversible and $182\mathrm{kJ}$of energy is liberated.

Correct the equation and then balance it:

$$\begin{gathered} \mathrm{Ca} +{\mathrm{H}}_2\mathrm{O} \to \mathrm{CaOH} +{\mathrm{H}}_2 \\ {\mathrm{N}}_{2 } +\mathrm{H} \to {\mathrm{NH}}_3 \end{gathered}$$

Identify the substance oxidised and oxidising agent in the following reaction:

${\mathrm{H}}_2\mathrm{S} + {\mathrm{Cl}}_2 \to \mathrm{S} +2\mathrm{HCl}$

Predict the oxidising agent and reducing agent in the following reaction:

$\mathrm{PbS}\left(\mathrm{s}\right) +4{\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{aq}\right) \to {\mathrm{PbSO}}_4\left(\mathrm{s}\right) +4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

Write the balanced equation for the following chemical reaction:

Aqueous solutions of sulphuric acid and sodium hydroxide react to form aqueous sodium sulphate and water.

Write the balanced equation for the following chemical reaction:

Phosphorus burns in chlorine gas to form phosphorus pentachloride.