Fact 1: Melting means changing from a solid into a liquid by adding heat energy.

Fact 2: When a substance melts, it changes phase from a solid to a liquid by the application of heat.

Given the two facts above, answer the question "What can be done to a solid by adding heat energy?" with the following options: 
- massive damage
 - phasing the bubbles
 - It expands
 - cooling the center
 - Evaporation
 - changing the phase
 - removing the air
 - Water expanding


 

      changing the phase   