What atoms make up water and how many of each are there?

1 Answer | Add Yours

shumbm's profile pic

Borys Shumyatskiy | College Teacher | (Level 3) Associate Educator

Posted on

Hello!

One molecule of water is made up of:

one atom of oxygen (`O` )

and

two atoms of hydrogen (`H` ).

The formula is therefore `H_2 O.`

The mass of one oxygen atom is about 16 times the mass of one hydrogen atom, so oxygen atom takes about `16/18 approx 89%` of water molecule's mass.

We’ve answered 318,928 questions. We can answer yours, too.

Ask a question