Question

How many molecules are present in 8 g of O2 molecule?

Answer 1

Answer:

⇒ 1 g contains → 0.188 × 1023 molecules of di oxygen. ∴ 8 g contains → 0.188 × 8 × 1023 molecules of di oxygen.

Explanation:

Answer 2

Answer:

First calculate ther number of moles of O2 using: moles = mass / relative molecular mass = 8 / 32 = 0.25.

For each molecule of O2, there are 2 oxygen atoms. Therefore moles of oxygen atoms = 2 x 0.25 = 0.5

1 mole of anything is 6.022 x 10^23 atoms (Avogadro constant)

So number of atoms = 0.5 x 6.022 x 10^23 = 3.011 x 10^23