Question

1. which phase changes occur when heat is added? select all that apply. vaporization condensation freezing melting

Explanation:

• Vaporization: Liquid to gas, requires heat (endothermic).
• Condensation: Gas to liquid, releases heat (exothermic), so not with added heat.
• Freezing: Liquid to solid, releases heat (exothermic), so not with added heat.
• Melting: Solid to liquid, requires heat (endothermic).

Answer:

• vaporization
• melting