Question

Which has greater number of atoms 40g of oxygen or 35g of hydrogen

Answer 1

40g of oxygen is havier

Answer 2

40g of oxygen will have more no. of atoms because in 40g of oxygen there will be 40 multiplied by avagadro no. of molecules and in one molecule there will be two atoms and the same condition will be in the case of 35g of hydrogen molecules.
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