Question

What happens when sodium hydroxide is added to aqueous sodium sulfite .

Answer 1

Sodium sulfite reacts with HCl to give you NaCl, SO2, and H2O:

Na2SO3 + 2HCl -> 2NaCl + SO2 + H2O

The SO2 will come off as a gas leaving a sodium chloride (table salt) solution behind.

Answer 2

This Rxn generates a big, foul, toxic, long-lasting stench! You also get some salt (NaCl), for your troubles, too. But it’s easier to buy some Morton’s salt for about 75 cents/lb.

The Sulfur Dioxide gas generated smells like rotten eggs and is toxic to humans and other living things