Question

Identify each of the phase changes described below. Liquid gold is poured into molds and cools to become solid bars. The gold is . Liquid nitrogen becomes a gas when it is poured out of its container. The nitrogen is . Solid iron is heated to high temperatures so that it becomes a liquid. The iron is . Water vapor in the air becomes tiny liquid droplets that form fog. The water is . In a very cold cryogenic freezer, solid oxygen forms on the walls from the oxygen gas in the air. The oxygen is . In the high desert, snow changes to water vapor without becoming liquid water. The snow is .

Answer 1

The gold is Freezing (or solidify).
The nitrogen is evaporating.
The iron is melting.
The water is condensing.
The oxygen is depositing. 
The water is sublimating.

Answer 2

Liquid gold is poured into molds and cools to become solid bars. The gold is "FREEZING"

Liquid nitrogen becomes a gas when it is poured out of its container. The nitrogen is "BOILING"

Solid iron is heated to high temperatures so that it becomes a liquid. The iron is "MELTING"

Water vapor in the air becomes tiny liquid droplets that form fog. The water is "CONDENSING'

In a very cold cryogenic freezer, solid oxygen forms on the walls from the oxygen gas in the air. The oxygen is "DEPOSITING"

In the high desert, snow changes to water vapor without becoming liquid water. The snow is "SUBLIMING"