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Question
Find the number of molecules in 73 g of HCl.
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Solution
HCl molecular mass = 1 + 35.5 = 36.5 g
36.5 g of HCl = 6.03 × 1023 molecules
∴ 73 g of molecules = `(6.03 xx 10^(23))/36.5 xx 73`
= 12.06 × 1023
= 1.2 × 1024
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