Question

Give reasons :

(a) Water is used as a cooling agent.

(b) Water pipes burst in severe winters.

(c) It is difficult to cook in hills as compared to plains.

(d) Ice floats on water.

(e) Sea water does not freeze at 0${}^{\circ }$C.

Answer 1

(a) Water has high speci c heat. Water neither heats up nor cools down quickly. This property makes
water as a excellent cooling agent.
(b) Water pipes bursts in severe winter because the water inside I the pipes freezes and increases its
volume.
(c) Water boils at a lower temperature in the hills, where the atmospheric pressure is lower than in the
plains. This is why it takes a longer time to cook in hilly regions.
(d) Ice has low density as compared to water. Water has maximum density at 4°C. That is why ice floats on water.
(e) There are impurities dissolved in sea water which increases the freezing point. That is why sea
water does not freeze at 0°C.