A $100 \mathrm{~mL}$ solution of $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{MgBr}$ on treatment with methanol produces $2.24 \mathrm{~mL}$ of a gas at STP. The weight of gas produced is _____________ mg. [nearest integer]
Answer (integer)
3
Solution
$$\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{MgBr}+\mathrm{CH}_{3} \mathrm{OH} \rightarrow \mathrm{CH}_{3}-\mathrm{CH}_{3}+\operatorname{MgBr}\left(\mathrm{OCH}_{3}\right)$$
<br/><br/>
As $2.24 \,\mathrm{ml}$ is formed at STP.
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Number of moles of ethane gas produced
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$=\frac{2.24 X}{22.4}$
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$=10^{-4}\, \mathrm{ml}$
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Mass of ethane produced $=10^{-4} \times 30=3 \times 10^{-}=3\mathrm{mg}$
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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