What are the products formed when sulphur dioxide dissolves in aqueous sodium hydroxide?
When dilute sulfur dioxide is absorbed into aqueous alkaline solutions, the following three reactions among others should be considered:
SO2 + H2O <--> H+ + HSO3O-
HSO3 - <--> H+ + SO3 ^(-2)
In sodium hydroxide, the following compounds are also produced:
SO2 + NaOH(aq) <--> SO3 ^(-2) + Na+ + H+
SO2 + 2NaOH(aq) <--> Na2SO3 + H2O
SO2 + NaOH(aq) <--> NaHSO3