Question

Assertion: Both chlorine and sulphur dioxide act as bleaching agents.
Reason: Chlorine bleaches by vigorous oxidation, while sulphur dioxide bleaches by mild reduction.

• A. It both Assertion and Reason are true and the Reason is a correct explanation of the Assertion
• B. If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion
• C. If Assertion is true but the Reason is false
• D. If both Assertion and Reason is false

Answer 1

Answer: (A)

$SO _{2}$ in presence of moisture acts as a bleaching agent. This is due to the reducing nature of $SO _{2}$. But bleaching action is only temporary.

$SO _{2}+2 H _{2} O \rightarrow H _{2} SO _{4}+2[ H ]$

Similarily, $Cl _{2}$ in presence of moisture give out nascent, oxygen and cause bleaching.

$Cl _{2}+ H _{2} O \rightarrow 2 HCl +[ O ]$

here bleaching action is permanent.