- Heat is a kind of heat energy
- Heat energy can change the state of matter
- So, heat can change the state of matter

- Heat can change the state of matter
- Liquid is a kind of state of matter
- Solid is a kind of state of matter
- Hence, heat can change a substance from a solid to liquid

- Heat can change a substance from a solid to liquid
- Melting means a substance changes from a solid into a liquid by increasing heat energy
- Therefore, heat can cause a solid substance to melt

- Heat can cause a solid substance to melt
- An ice cube is a kind of solid
- Therefore, heat can cause the ice cube to melt

Hence, heat can cause the ice cube to melt
Q: What form of energy causes an ice cube to melt?
Context:
- Heat is a kind of heat energy 
- Liquid is a kind of state of matter 
- Heat energy can change the state of matter 
- Solid is a kind of state of matter 
- Melting means a substance changes from a solid into a liquid by increasing heat energy 
- An ice cube is a kind of solid