Question

Refer to the plot of temperature versus time showing the changes in the state of ice on heating (not to scale).

Which of the following is correct ?

• A. $AB$ represents ice and water are not in the thermal equilibrium
• B. At $B$ water starts boiling
• C. At $C$ all the water gets converted into steam
• D. $CD$ represents water and steam in equilibrium at boiling point

Answer 1

Answer: (D)

In the given graph, $AB$ represents no change in temperature with time. It means ice and water are in thermal equilibrium. $BC$ shows the change in temperature with time. $CD$ represents a constant temperature $(100^{\circ}C)$ with time. It means, water and steam are in thermal equilibrium at boiling point.