Question

Rubbing alcohol evaporates from your arm quickly, leaving a cooling effect on your skin. How do the molecules of gas compare to the molecules as a liquid?

A. The gas particles move faster, have the same molecular composition, and have weaker attractions between them than the liquid particles.
B. The gas particles move faster than the liquid particles, and the bonds of the molecules are broken during evaporation to allow gas atoms to spread apart.
C. The gas particles move slower but have the same molecular structure and the same attraction between them as the liquid particles.
D. The gas and liquid particles move at the same speed, but the bonds of the molecules are broken during evaporation to allow the gas atoms to spread apart.

Answer 1

Answer : (A) The gas particles moves faster, have the same molecular composition, and have weaker attractions between them than the liquid particles.

Explanation : As we know Evaporation is a cooling process because during evaporation the particles of liquid absorb energy from the surroundings and this absorption of energy lost during evaporation and surrounding get cooler.

Alcohol is the volatile substance which easily vaporises, it absorb heat from our hand and gets converted into gaseous form. That is why we feel cooling on our skin.

The intermolecular forces of attraction in gases is weaker as compared to the liquids. So the molecules of gases can move very fast as compared to liquids.

Answer 2

The answer is option A "The gas particles move faster, have the same molecular composition, and have weaker attractions between them than the liquid particles." Some differences between a gas and a liquid is their physical characteristics, and also gas molecules move faster then liquids. Just like how liquid molecules move faster then solid molecules.

Hope this helps.