Question

1. what happens to a liquid when it is heated? a) it freezes into a solid b) it evaporates into gas c) it condenses into a liquid d) it remains unchanged 4. which muscle helps us breathe by moving up and down? a) melting b) freezing c) evaporation d) condensation

Explanation:

1. When a liquid is heated, it gains energy and its molecules move faster. Eventually, it changes state from liquid to gas through evaporation. Freezing is the change from liquid to solid (opposite of heating), condensation is gas to liquid, and a liquid doesn't remain unchanged when heated significantly.
2. The options for the second - question seem to be wrong as they are phase - change processes instead of muscles. But if we focus on the first question: Heating a liquid causes evaporation.

Answer:

1. b) It evaporates into gas