SAT Subject Physics Practice Question 326: Answer and Explanation
22. A 50 g cube of ice is added to 500 g of boiling water. Which of the following is most likely to occur?
A. The ice cube vaporizes before it strikes the bottom of the container.
B. The water boils more vigorously because the hot water draws cold from the ice cube.
C. The water in the container stops boiling during the phase change of the ice to water.
D. The more dense ice cube sinks in the less dense hot water.
E. Steam bubbles form on the ice cube.
Correct Answer: C
The correct answer is (C). When the ice cube enters the boiling water, the heat in the water immediately begins to change the phase of the ice to water. Consequently, the higher energy phase change (boiling) stops until the lower energy phase change (melting) is complete.