Question: how many molecules are there in 2 moles of h2o?
Answer: Therefore 2 mole H2O will have 2.4088×10^24 hydrogen atoms. Since one mole is defined as 6.022 x 10^23, and there are two hydrogen per molecule, that would mean that there are exactly 12.044 x 10^23 molecules of hydrogen in one mole of water.