Question

Sulphuric acid is produced by complex industrial processes like contact process.Why sulphuric acid cannot be produced through the protonaction of sulphate ions, for example, by mixing HCl and Na2SO4.

After mixing the salt and acid, concentrated sulphuric acid can be produced by heating up the liquid.However, this method is not commonly used, or not even used, why?

Answer 1

Sulfuric acid cannot be produced by mixing HCl with Na2SO4 because the reaction produces sulfurous acid, which decomposes upon heating instead of forming sulfuric acid. The Contact Process is the preferred industrial method to produce high purity sulfuric acid.

Step-by-step explanation:

The idea of producing sulfuric acid by simply mixing hydrochloric acid (HCl) with sodium sulfate (Na2SO4) and then heating is flawed because it does not take into account the chemical properties of these substances. When you mix HCl with Na2SO4, you get sodium chloride (NaCl) and sulfurous acid (H2SO3), not sulfuric acid (H2SO4). As sulfurous acid is unstable and can decompose into water and sulfur dioxide gas upon heating, this will not lead to the production of sulfuric acid.

To actually produce sulfuric acid, the Contact Process is used, which involves the oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3) in the presence of a catalyst and then its subsequent absorption in water to form sulfuric acid. This process ensures the formation of high purity sulfuric acid which is not achievable by simple acid-base reactions and heating.