Question

Using an equation, explain how sulphur(iv)oxide reacts with each of the following:

I) potasiumhydroxide solution
II) concentrated trioxonitrate(v) acid​

Answer 1

I) Sulphur dioxide gas reacts with potassium hydroxide solution in the following equation:

SO2(g) + 2KOH(aq) → K2SO3(aq) + H2O(l)

In this reaction, the sulphur dioxide reacts with the potassium hydroxide to form potassium sulphite and water. The reaction is a neutralization reaction, as the potassium hydroxide is a base and the sulphur dioxide is an acidic oxide.

II) Sulphur dioxide gas reacts with concentrated trioxonitrate(V) acid in the following equation:

SO2(g) + HNO3(l) → H2SO4(l) + NO2(g)

In this reaction, the sulphur dioxide reacts with the concentrated trioxonitrate(V) acid to form sulphuric acid and nitrogen dioxide gas. This is an oxidation-reduction reaction, as the sulphur dioxide is oxidized to sulphuric acid, while the trioxonitrate(V) acid is reduced to nitrogen dioxide gas. The reaction is also exothermic, meaning it releases heat.