When water exposed to the air changes from liquid to gas

What Can you be more clear --Molecules change it from being less dense

Yes it does because when the water is heated up or something is changes from a liquid to a gas.

The correct answer is B, 'the same type of atom'. By definition, an element is a single type of atom. They are the most basic forms of matter, and so they cannot be more than one kind of atom, and they also cannot be a compound, since compounds are made up of multiple atoms.

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