Question

A hydrocarbon contains 80% of carbon, then the
hydrocarbon is -
(1) CH4 (2) C2H4 (3) C2H6 (4) C2H2​

Answer 1

$\huge\textsf{Solution:}$

$\large\underline{\underline{\sf Ur\:Answer\:is\:C_2H_6}}$

$\large\underline{\underline{\sf Explanation:}}$

Total mass of $\sf{C_2H_6}$ is 30 u

C = 12 × 2 = 24 u

H = 1 × 6 = 6 u

Carbon contributes its 24u from total 30u.

•°• % will be $\large\implies{\sf \dfrac{24}{30}×100 }$

$\large\implies{\sf 80}$%

Hence ,

our answer is $\sf{C_2H_6}$

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Let's see of others too ,

$\large\underline{\underline{\sf In\:CH_4:}}$

Total mass of $\sf{CH_4}$ is 16

C = 12 × 1 = 12u

H = 4 × 1 = 4u

Carbon contributes its 12u from total 16

•°•

% will be $\large\implies{\sf \dfrac{12}{16}×100 }$

$\large\implies{\sf 75 }$%

$\LARGE\underline{\underline{\sf In\:C_2H_4:}}$

Total mass = 28u

C = 12 × 2 = 24u

H = 1 × 4 = 4u

Carbon contributes its 24u from total 28u

•°•

% will be $\large\implies{\sf \dfrac{24}{28}×100 }$

$\large\implies{\sf 85}$%

$\LARGE\underline{\underline{\sf C_2H_2:}}$

Total mass = 26u

C = 12 × 2 = 24u

H = 1 × 2 = 2u

Carbon contributes its 24u from total 26u

•°•

% will be $\large\implies{\sf \dfrac{24}{26}×100 }$

$\large\implies{\sf 92}$%

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