JEE Main · 2022 · 26 Jun 2022 · Shift 1 · Some Basic Concepts of Chemistry

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On complete combustion 0.30 g of an organic compound gave 0.20 g of carbon dioxide and 0.10 g of water. The percentage of carbon in the given organic compound is ______ (Nearest Integer)

Answer: 18

Solution

From combustion data: moles of

CO_{2} = 0.20/44 = 0.00455

mol, moles of

H_{2} O = 0.10/18 = 0.00556

mol. Mass of C in compound =

0.00455 \times 12 = 0.0545

g. Percentage of C =

(0.0545/0.30) \times 100 = 18.2%

, which rounds to 18%.

JEE Main · 2022 · 26 Jun 2022 · Shift 1 · Integer answer

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