Question

If one mole of oxygen atoms weighs 16 grams, calculate the mass of one atom of oxygen (in grams).

Answer 1

Mole: Mole can be defined as the amount of substance that contains the same number of entities (atoms, molecules, ions etc) as the number of atoms present in 12g of the carbon−12 isotope.

1 mole of oxygen contain$=6.022\times {10}^{23}\mathrm{atoms}$

$6.022\times {10}^{23}\mathrm{atoms}$ of oxygen have mass = 16 g

1 atom of oxygen has mass $=\frac{16}{6.022\times {10}^{23}}=2.657\times {10}^{-23}\mathrm{g}$

Hence the mass of an atom of oxygen in grams is $2.657\times {10}^{-23}\mathrm{g}$