Question

drag the missing word into place
as the heat rose, the water began to into the air.
matter state evaporate

Explanation:

The sentence describes a physical process where water changes its state due to heat. The word "evaporate" means to turn from liquid into vapor, which fits the context of water turning into air (vapor) as heat rises. "Matter" refers to physical substance in general, and "state" refers to a condition or mode of being, neither of which fit the action described in the sentence.

Answer:

evaporate