When dry ice changes into carbon dioxide, gas particles become larger. True or False?

False. The correct sentence will be" when the dry ice changes to carbon dioxide the molecules separates out leading to the expansion of volume"

Dry Ice *IS* Carbon Dioxide

Dry Ice is simply frozen Carbon Dioxide. It "melts" to become a gas in much the same way as normal ice first melts and then if you continue to heat it, it becomes steam. It's just that Dry Ice goes through a very short liquid phase - in effect it goes straight from solid to gas.

Carbon Dioxide is made up of molecule of CO2 (two Oxygen atoms bonded to one Carbon atom). These don't change size. It's only the space between molecules that changes: in a gas the molecules are much further apart and free to move around a lot more than in a solid.

It's false, the atomic radius doesn't change going from a solid to a gas, the only thing that changes is the space between each molecule.