Easy INTEGER +4 / -1 PYQ · JEE Mains 2022

Blister copper is produced by reaction of copper oxide with copper sulphide.

2Cu2O + Cu2S $\to$ 6Cu + SO2

When 2.86 $\times$ 103 g of Cu2O and 4.77 $\times$ 103 g of Cu2S are used for reaction, the mass of copper produced is _____________ g. (nearest integer)

(Atomic mass of Cu = 63.5 a.m. u, S = 32.0 a.m. u, O = 16.0 a.m. u)

Answer (integer) 3810

Solution

moles of $\mathrm{Cu}_{2} \mathrm{O}=\frac{2.86 \times 10^{3}}{143}=20$ <br/><br/> moles of $\mathrm{Cu}_{2} \mathrm{S}=\frac{4.77 \times 10^{3}}{159}=30$ <br/><br/> $\mathrm{Cu}_{2} \mathrm{O}$ is limiting reagent <br/><br/> $$ \begin{array}{lccc} 2 \mathrm{Cu}_{2} \mathrm{O} & + & \mathrm{Cu}_{2} \mathrm{~S} \longrightarrow & 6 \mathrm{Cu} & + & \mathrm{SO}_{2} \\ 20 && 30 & - & & - \\ - & &20 & 60 & & 10 \end{array} $$ <br/><br/> Mass of copper $=60 \times 63.5=3810 \mathrm{~g}$

About this question

Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept

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