Answer to Question #166686 in General Chemistry for Luxlakna Nith

Question

When we performed an acetaldehyde test in the presence of Na₂SO₃ the production of CO₂ was very low. why?

Answer 1

This is the sulfite method. The sulfite method is based on the property of aldehydes to form a bisulfite compound with sodium sulfite with the release of caustic soda

CH₃CHO+Na₂SO₃+H₂O = CH₃CH(OH)SO₃Na+NaOH

in this reaction, carbon dioxide is not formed at all