Question

Write a short note.

Anomalous behaviour of water

Write a short note.

Anomalous behaviour

Answer 1

1. Normally, liquids expand on heating and contract on cooling. But water exhibits an exceptional behaviour in a temperature range of 0 °C to 4 °C.
2. When water is heated from 0 °C up to 4 °C, instead of expanding, it contracts. Its volume decreases continuously from 0 °C to 4 °C. At 4°C, its volume is minimum.
3. Upon heating further, however, it expands and its volume increases.
4. This behaviour of water between a temperature interval of 0°C to 4°C is called anomalous behaviour of water.
5. Phenomena observed due to anomalous behaviour of water are:
   • Survival of aquatic life in cold regions
   • Cracking of rocks in winter
   • Breaking of pipes for water supply in a cold region.