But the chemical equation of water vapor is the same as for liquid water. It’s still H2O. There is no chemical reaction when a substances boils or evaporates. read more
The chemical formula for water is H[math]_2[/math]O. It does not matter whether it's solid, liquid or gas. Chemists would denote this by adding the letter s, l or g in brackets after the formula. read more
Quick Answer. The chemical formula for water vapor is H 2 O.Water is a unique compound because it has the ability to exist on the earth's surface in all three forms: liquid, solid (ice), and gas (water vapor). read more