Question

A substance that goes through phase change starts as a solid. as it is heated, the substance exists as a __1__. when the substance is completely melted, its temperature will increase until it reaches the __2__ point. after the substance has finished boiling, it will exist as a __3__.

Answer 1

1: if the solid is heating and is not yet to the melting point, the answer would be "solid". If the substance reached the melting point and is heating up at that point, the answer would be "solid and liquid" (yes, at the same time).

2. boiling point.

Once the substance is melted completely into a liquid, the highest point where the substance will still exist as a liquid would be the boiling point.

3. gas.

The three main states of matter from cooler to hotter are:

solid, liquid, and gas.