Q1 / 180 · KCET 2020 · Chemistry

Copper is extracted from copper pyrites by

  • A
    thermal decomposition
  • B
    reduction by coke
  • C
    electrometallurgy
  • Correct answer
    D
    auto reduction

Solution

Copper is extracted from copper pyrites by auto reduction process in the following manner. $\begin{aligned} 2 \mathrm{CuFeS}_{2}+\mathrm{O}_{2} & \longrightarrow \mathrm{Cu}_{2} \mathrm{~S}+2 \mathrm{FeS}+\mathrm{SO}_{2} \\ 2 \mathrm{FeS}+3 \mathrm{O}_{2} & \longrightarrow 2 \mathrm{FeO}+2 \mathrm{SO}_{2} \\ \mathrm{FeO}+\mathrm{SiO}_{2} & \longrightarrow \mathrm{FeSiO}_{3} \\ 2 \mathrm{Cu}_{2} \mathrm{~S}+3 \mathrm{O}_{2} & \longrightarrow 2 \mathrm{Cu}_{2} \mathrm{O}+2 \mathrm{SO}_{2} \\ 2 \mathrm{Cu}_{2} \mathrm{O}+\mathrm{Cu}_{2} \mathrm{~S} \longrightarrow 6 \mathrm{Cu}+\mathrm{SO}_{2} \end{aligned}$

Hence, the correct answer is option: 'D'.

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