An organic compound is subjected to chlorination to get compound A using 5.0 g of chlorine. When 0.5 g of compound A is reacted with \(\mathrm{AgNO}_{3}\) [Carius Method], the percentage of chlorine in compound A is ______ when it forms 0.3849 g of AgCl (Round off to the Nearest integer) (Atomic masses of Ag and Cl are 107.87 and 35.5 respectively)

JEE Main · 2021 · 27 Jul 2021 · Shift 1 · Practical and Analytical Chemistry

An organic compound is subjected to chlorination to get compound A using 5.0 g of chlorine. When 0.5 g of compound A is reacted with

AgNO_{3}

[Carius Method], the percentage of chlorine in compound A is ______ when it forms 0.3849 g of AgCl
(Round off to the Nearest integer)
(Atomic masses of Ag and Cl are 107.87 and 35.5 respectively)

Answer: 19

Solution

In the Carius estimation every chlorine atom of the organic compound ends up as silver chloride, so one mole of AgCl corresponds to one mole of chlorine in the sample.

M (AgCl) = 107.87 + 35.5 = 143.37 g mo l^{- 1}

The chlorine contained in

0.3849

g of AgCl is

m_{Cl} = \frac{35.5}{143.37} \times 0.3849 = 0.0953 g

All of it came from the

0.5

g portion of compound A taken for the estimation, so

% Cl = \frac{0.0953}{0.5} \times 100 = 19.06

The chlorine spent in the chlorination step does not enter this balance, because the estimation compares only the AgCl formed with the mass of A taken for the analysis. Rounded to the nearest integer, the chlorine content of compound A is

19%

JEE Main · 2021 · 27 Jul 2021 · Shift 1 · Integer answer

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JEE Main · 2021 · 27 Jul 2021 · Shift 1 · Practical and Analytical Chemistry

Solution

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