Calculate the number of atoms in 60 g of neon [Ne = 20]

Gram atomic mass of Ne = 20 g

As, 1 mole of Ne weighs 20 g and has 6.023 x 10²³ atoms

So, 60 g of Ne will have

$\dfrac{ 6.023 \times 10^{23}}{20} \times 60 \\[0.5em] = \dfrac{60}{20} \times 6.023 \times 10^{23} \\[0.5em] = 3 \times 6.023 \times 10^{23} \text{ atoms}$

Hence, number of atoms in 60 g of Ne = 3 x 6.023 x 10²³ atoms