Question

give a reason why concentrated and not dilute sulphuric acid behaves as an oxidizing and a dehydrating agent

Answer 1

dilute contains some %age of water

Answer 2

ANSWER

Concentrated sulphuric acid behaves as a strong dehydrating agent as the hydration reaction is highly exothermic. It has strong affinity for water removing water molecules from other compounds.

It has a strong oxidising property as when it reacts with metals produces sulphur dioxide,water and sulphate ions while dilute sulphuric acid produces hydrogen and salt.