Multiple choice

What is rust?

  1. It is an oxide of chromium.

  2. It is aluminium cholride.

  3. It is ferric chloride.

  4. It is a reddish brown hydrated oxide of iron.

  5. None of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Rust is a reddish brown hydrated oxide of iron. It is formed when iron is exposed to oxygen in the presence of moisture.