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 ?

Options

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

D

Explanation

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