Calculate number of atoms in 52g of Helium

The molar mass that is the mass of 6.022 X 10^{23} atoms of helium is 4g.

Hence 1 mole of He = 4 g of He = 6.022 X 10^{23} atoms of He

1 g of He = (6.022 X 10^{23}) / 4 atoms of He

52 g of He = (6.022 X 10^{23}X 52^{ }) / 4 atoms of He

= 7.829 X 10^{24} atoms of He

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