Question

Which of the following quantity does not always expand on heating?

• A. Iron tracks
• B. Water
• C. Oil
• D. Copper wire

Answer 1

The correct option is B

Water

Generally, liquids expand on heating & contract on cooling. Water, however, shows an exceptional behavior below 4${}^{\circ }C$. If we cool water at room temperature we find that it goes on contracting but as the temperature falls below 4${}^{\circ }C$ it begins to expand instead of contracting, conversely if water is heated from 0-degree centigrade to 4${}^{\circ }C$ instead of expanding it contracts.