Question

How would I calculate the number of moles of Hydrogen in a given mass of water?

Answer 1

#of moles = mass/ molecular weight. in water: molarity= moles * volume

Answer 2

So would that be say, 7 grams of H2O x ( 1 mole of H2O/18 grams of H20) X (2 molecules of Hydrogen/ 1 mole of H20) ?

Answer 3

well since you're not diluting anything or titrating you find the ratio of H2O. Let's say you have 7g of H20. The MW for H2O is 18 per mole. so 7/18= 0.39 moles of H2O. Then, to calculate mol H, partial mol/total, which is 0.39. in H20, we have 2 moles of H per 1 H2O, so we have 0.76 mol of Hydrogen in 7 grams of water