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Question
If the relative molecular mass of A is 90, what is the molecular formula of A?
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Solution
The relative molecular mass of A is 90
Empirical Formula mass of compound is = 45
Then, n = Molecular mass/ Empirical Formula Mass
= 90/45 = 2
Molecular formula of compound = n x Empirical formula
= 2 x (CO2H) = C2O4H2.
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