Question

for a substance to change from a gas to a liquid, what must happen to its particles?
a. they must lose enough of their kinetic energy so that the attractions between them hold in place as they vibrate.
b. they must lose enough of their kinetic energy that their motion is influenced by the attractions between them.
c. they must gain enough kinetic energy to break out of their rigid structure and move independently.
d. they must gain enough kinetic energy to allow them to move freely while still being attracted to one another.

Explanation:

In a gas - to - liquid phase change (condensation), particles lose kinetic energy. As they lose energy, the intermolecular attractions start to have a more significant influence on their motion. In a gas, particles move freely with high kinetic energy and weak intermolecular forces having little effect. In a liquid, the motion of particles is more restricted due to intermolecular forces, but they can still move past each other.

Answer:

B. They must lose enough of their kinetic energy that their motion is influenced by the attractions between them.