Answer:
# 5
Explanation:
The question describes silver being "poured" into a mold and cools to become a solid bar. This is the phase of liquid to solid. When a element cools down below it's freezing points to become a solid.
Liquid to Solid Definition:
Freezing, or solidification, is a phase transition in which a liquid turns into a solid when its temperature is lowered to or below its freezing point. All known liquids, except helium, freeze when the temperature is low enough.