JEE Main202331 Jan 2023Evening ShiftChemistrySome Basic Concepts of ChemistryActual

When a hydrocarbon A undergoes complete combustion it requires 11 equivalents of oxygen and produces 4 equivalents of water. What is the molecular formula of A ?

Options

AC 11 H 8
BC 11 H 4
CC 5 H 8
DC 9 H 8

Correct answer

D. C 9 H 8

Step-by-step solution

By using the formula of combustion analysis: C x H y + x + y 4 O 2 → CO 2 + y 2 H 2 O Given, x + y 4 a = 11 a x + y 4 = 11 y 2 a = 4 a y = 8 , then x + 8 4 = 11 x   =   11 - 8 4 x = 9 Formula = C 9 H 8

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