Question

combustion of coal releases sulfur dioxide into the atmosphere the following process converts this gas into sulfuric acid a component of acid rain. If each tonne of coal produces 1.4 x 10⁴ L of sulfur dioxide (measured at STP)what mass of sulfuric acid can result from combustion of each tonne of coal? (1 tonne = 1000 kg)

Answer 1

Since in atmosphere SO2 react with O2 (oxygen) at high temperature at the time of lighting to form SO3 (sulphur trioxide) which further react with water to form H2SO4 (sulphuric acid)

Reaction

2SO2 + O2 ---------- 2SO3

SO3 + H2O ---------- H2SO4

At industry level these reactions take place as

First sulphur is burn in presence of oxygen to form sulphur dioxide which is then prurified and then these sulphur dioxide react with oxygen in the presence of vanadium pentaoxpe at 1-2 ATM pressure 450°c to form sulphur trioxide . These sulphur trioxide react with sulphuric acid to form oleum (H2S2O7) which further react water to form sulphuric acid

Reaction

S + O2 --------- SO2

2SO2 + O2 --------- in presence of V2O5 at 1-2 atm 450°c 2SO3

SO3 + H2SO4 ---------- H2S2O7

H2S2O7 + H2O ----------- 2H2SO4

One tonne of coal produce 1.4 × 10^4 L

At stp one mole of gas occupy 22.4 L space

So no of mole of sulphur produce will be equal to

1.4×10^4/ 22.4

= 6.25 × 10^2 mole

One mole of sulphur produce one mole of sulphur dioxide

6.25 × 10^2 mole of sulphur will produce 6.25×10^2 mole of SO2

Two mole of sulphur dioxide produce 2 mole of SO3

6.25×10^2 mole of SO2 will produce 6.25×10^2 mole of SO3

One mole of SO3 produce 1 mole of sulphuric acid

6.25 × 10^2 mole of SO3 produce 6.25 × 10^2 mole of sulphuric acid