Answer: Physical change.
Explanation: A physical change is one where the chemical formula of a substance is not changed. Steam is H2O and so is room temperature water.
A good example of a physical change is ripping a piece of paper in half. The shape of the piece of paper has changed, but it's chemical makeup has stayed the same.
A good example of a chemical change is burning a piece of paper. The paper has now turned to ash, which is a different chemical substance than paper.
Note: It is important to remember, nothing new is created and nothing is ever destroyed! In all chemical reactions, the same amount of atoms of each element comes out at the end of the reaction. The elements themselves are not changed however the way they are arranged is.