1 mole of water molecules has 2 hydrogen atoms and one oxygen atom.
What is a mole?
A mole (mol) is the amount of a substance that contains 6.02 × 10 23 representative particles of that substance. The mole is the SI unit for the amount of a substance. There are, therefore, 6.02 × 10 23 water molecules in a mole of water molecules. Water (H2O) is made from 2 atoms of hydrogen and 1 atom of oxygen. A mole of water molecules would be 2 moles of hydrogen atoms plus 1mole of oxygen atoms. One mole of water weighs 18.0152 grams.