Question

$Al$ is more reactive than iron but it is less easily corroded than iron because :

• A. it is a noble metal
• B. oxygen forms a protective oxide layer
• C. iron undergoes easily reaction with water
• D. iron formsmono and divalent ion

Answer 1

Answer: (B)

oxygen forms a protective oxide layer

Aluminum unlike iron ,does not corrode in moist conditions. Its surface is protected by layer of aluminium oxide. This prevents thealluminium to come in contact with air and oxygen. The layer of aluminium oxide do not vanish, unlike rust which can flake off the surface of iron and steel objects. So $Al$ is covered with a layer by the oxygen

Hence option B is correct.