A chunk of ice T 20degreeC is added to a thermally insulate

A chunk of ice (T = -20degreeC) is added to a thermally insulated container of cold water (T = 0degreeC). What happens in the container? The ice melts until thermal equilibrium is established. Some of the water freezes and the chunk of ice get larger. The water cools down until thermal equilibrium is established. None of the above things happen.

Solution

Some of the water freezes and the chunk of ice gets larger.

Since water have both phases at 0 ^o C i.e., water and ice