Question

When a solid is placed in a container and heat is applied, a phase change occurs. Watch the video and identify which of the following statements are correct.

a) The temperature increases while all of a liquid is converted to a gas.
b) The average kinetic energy of the system changes while all of a solid is converted to a liquid.
c) Temperature remains constant while all of a solid is converted to a liquid.
d) When heat is applied to a solid, the molecular motion decreases as the temperature increases.
e) When a solid is converted to a liquid, heat is absorbed.

Answer 1

Temperature remains constant while all of a solid is converted to a liquid.

When a solid is converted to a liquid, heat is absorbed.

Step-by-step explanation:

During a phase change, the temperature of the system remains constant. Recall that latent heat is defined as heat that causes a change of state without a corresponding rise in temperature of the system.

When a solid is converted to a liquid, latent heat of fusion is involved hence the temperature of the system remains constant throughout the process.

Similarly, heat is absorbed as intermolecular forces are broken up and the would converts to liquid.