Question

Calculate the no: of atoms and molecules in 18g H20 (Water)

Answer 1

Explanation:

Molecular mass of water is 18g/mol so it's 1mol. So we have 1.8066*10^24 atoms in 18g of water.

Now, 1 molecule of water contains 2 atoms of hydrogen and 1 atom of oxygen i.e. 3 atoms. Therefore 6.023 × 10²³ molecules contain 6.023 × 10²³ × 3 = 1.8069 × 10²⁴ atoms. Therefore 18 gm of water contains 1.8069 × 10²⁴ atoms.

there're about 6.023 x 10^23 molecules in 18g of water .

Hope this helps mate.