Write the conditions to maximise the yield of sulphuric acid by contact process.

Explanation

The key step in the production of `H_2SO_4` is the oxidation of `SO_2` to `SO_3` in the presence of catalyst, `V_2O_5`.
`SO_2(g)+O_2(g) harr 2SO_3(g), DeltaH_f^@ = -196.6 kJ mol^(-1)`
This reaction is exothermic, reversible and forward reaction that leads to a decrease in volume. Therefore, low temperature and high pressure are the favourable conditions for maximum yield.