A cylinder at left with balls stacked near the bottom of the cylinder has an arrow leading to a cylinder at right cylinder with balls in a layer on the bottom of the cylinder.

Question

How is energy related to the change of state represented by the model?

Atoms gain energy as a solid changes to a liquid.
Atoms gain energy as a solid changes to a gas.
Atoms lose energy as a solid changes to a liquid.
Atoms lose energy as a solid changes to a gas.

Answer 1

The change of state represented by the model involves a transition between different phases of matter. Here's how energy is related to these changes:

1. Atoms gain energy as a solid changes to a liquid: This is an accurate statement. When a solid melts to become a liquid, the atoms absorb energy in the form of heat. This energy allows the atoms to move more freely, breaking the rigid structure of the solid.

2. Atoms gain energy as a solid changes to a gas: This is also true. When a solid undergoes sublimation (directly changing from solid to gas) or when it melts and then vaporizes, energy is absorbed.

3. Atoms lose energy as a solid changes to a liquid: This statement is incorrect. A solid does not lose energy when it changes to a liquid; rather, it gains energy.

4. Atoms lose energy as a solid changes to a gas: This is also incorrect. During the transition from solid to gas, energy is still absorbed.

In summary, for the transitions from solid to liquid and solid to gas, the concept is that atoms gain energy. Therefore, the first two statements correctly represent the relationship of energy to change of state in the described model.