Calculate the number of molecules of sulphur (S8) present in 16g of solid sulphur (Atomic mass of S = 32)


The molecular formula of sulphur is given to be S8. It contains 8 atoms of sulphur.

The molecular mass of sulphur molecule = 32 x 8 = 256u.


Therefore, 1 mole of sulphur molecules = 256 g


Now, 256g of sulphur = 1 mole of sulphur molecules


Hence, 16g of sulphur = 16/256 mole of sulphur molecules = 0.0625 moles of Sulphur molecules


Also, 1 mole of sulphur molecules = 6.023 x 1023 molecules


0.0625 mole of sulphur molecules = 6.023 x 1023 x 0.0625 molecules = 3.76 x 1022 molecules


Therefore, the number of molecules present in 16 g sulphur is 3.76 x 1022


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