They became larger in size. They spread out into the air. They were absorbed by the glass. They passed through the glass into the air.
I gave my students this multiple choice question: Chris left a glass of water on a windowsill. When he looked at the glass a few days later, some of the water had evaporated. Which of the following best describes what happened to the particles of water that evaporated?

Only one answer is correct among these 4 choices:
- They became larger in size.
- They spread out into the air.
- They were absorbed by the glass.
- They passed through the glass into the air.

Could you tell me which one is correct?

They spread out into the air.