Question

possible points: 1
as a substance changes state from a solid, to a liquid, to a gas, does its density change?
no. the density does not change since all that changes is the temperature of the molecules.
yes. it changes because mass changes for each state while volume does not change, so the end result will be a different value for density
no. the density does not change because both mass and volume of a substance change proportionally when you change states.
yes. it changes due to the fact that as a substance goes from a solid to liquid to gas, the molecules move further and further apart

Explanation:

Density is defined as $\frac{\text{mass}}{\text{volume}}$. The mass of a fixed amount of substance stays constant across state changes, but volume increases significantly as it moves from solid → liquid → gas because molecules spread out. This causes density to decrease, so density does change between these states.

Answer:

Yes. It changes due to the fact that as a substance goes from a solid to liquid to gas, the molecules move further and further apart