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Question
The molecular formula for elemental sulphur is S8.In a sample of 5.12 g of sulphur:
How many molecules and atoms are present?
Solution
Number atoms 1 mole S8 = (6.02 x 1023) x 8
∴ Number of atoms in 0.02 mole S8 = 0.02 x 8 x (6.02 x 1023)
= 9.632 x 1022
Number of molecules in 0.02 (S8) = 0.02 x 6.02 x 1023
= 1.204 x 1022
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