Calculate the weight percentage of hydrogen in water. ?

Question

Does anyone know how to do this? If so, can you please explain because I have a lot of these on my homework! thanks!

Answer 1

Water has the formula H2O.

1)Find the Mr of water.To do this add up the masses of each atom in the water molecule:

     H2O = 2 + 16 = 18g

2)Now determine the mass of an atom of hydrogen (H).

      1 H atom = 1 g

2)Determine the amount of H atoms present in water

     2H atoms

3)      1 H atom = 1g

         2 H atoms = 2g

4)To find a percentage put the mass of Hatoms over the total mass of water and multiply by 100%.

       2/18 * 100 = 11.1%

Good Luck.

Answer 2

Water = H2O (2 hydrogens, 1 oxygen)

(Molecular) Mass of Hydrogen = 1.01

Oxygen = 16.00

Total mass of water = 18.02

So mass of hydrogen is 2.02/18.02

=11.21%

Answer 3

~11.2 %