Multiple choice

Which of the following changes cannot be reversed?

  1. Production of charcoal

  2. Dissolving salt in water

  3. Boiling of water

  4. Melting of ice

  5. Melting wax

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

Charcoal is obtained by heating of wood, sugar, etc. in the absence of oxygen, which cannot be reversed.