- Gas is a kind of state of matter
- Liquid is a kind of state of matter
- Heat energy can change the state of matter
- Therefore, heat energy can change a substance from a liquid to a gas

- Heat energy can change a substance from a liquid to a gas
- Water is a kind of substance
- Hence, heat energy can change water from a liquid to a gas

Therefore, heat energy can change water from a liquid to a gas
Question: Which form of energy is needed to change water from a liquid to a gas?
Context: - Gas is a kind of state of matter 
- Water is a kind of substance 
- Liquid is a kind of state of matter 
- Heat energy can change the state of matter