Question

An organic compound on analysis gave H = 6.48% and O = 51.42%. Determine it’s empirical formula if the compound contains 12 atoms of carbon. [C = 12, H = 1, O = 16]

August 2, 2024

Answer

Element	% composition	At. wt.	Relative no. of atoms	Simplest ratio
Oxygen	51.42	16	= 3.213	= 1
Hydrogen	6.48	1	= 6.48	= 2.016 = 2
Carbon	100 – (51.42 + 6.48) = 42.1	12	= 3.508	= 1.091 = 1

Simplest ratio of whole numbers = O : H : C = 1 : 2 : 1

As number of carbon atoms = 12

Therefore, O : H : C = 12 : 24 : 12

Hence, empirical formula is C₁₂H₂₄O₁₂

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