Question

Which of the following is correctly matched:-
A.Copper matte \[ \to \]$Cu$ - self- reduction
B.Hematite \[ \to \] pig iron - blast furnace
C.Conc. Galena \[ \to \] $PbO$ - calcination
D.Red bauxite \[ \to \] pure $Al$ - electrolytic reduction

Answer 1

Hint: We have to remember that the copper matte is containing copper sulphide and iron sulphide and the copper can be extracted from copper matte by reduction method. And hematite is a mineral which contains ferric oxide. The galena is also a natural mineral and it consists of lead. And the red bauxite is also known as bauxite residue and it contains different oxide compounds.

Complete answer:
We must know that in self – reduction, there does not want any external reducing agents. And here, the copper matte is undergoing self- reduction. Because, all the metals are electropositive. Thus, it can be obtained by the method of self- reduction.
Here, the copper matte eliminates the sulphur dioxide by self- reduction and there is a formation of Copper metal. Therefore, copper matte \[ \to \]$Cu$ - self- reduction is correctly matched. Hence, option (A) is correct.
The hematite is used for the preparation of iron. And the pig iron is formed as an intermediate product from the production of iron by using a blast furnace. The pig iron is formed by the smelting process. Therefore we can say that, Hematite \[ \to \] pig iron - blast furnace is matching correctly. Hence, option (B) is correct.
The concentrated galena is a sulphide ore and there is a formation of lead by the self -reduction process of conc. Galena and the reaction can be written as
\[2PbS + 3{O_2} \to 2PbO + 2S{O_2}\]
\[PbS + 2PbO \to 3Pb + S{O_2}\]
But here, the calcination method is not used for the preparation of lead from galena and the lead is obtained by self – reduction. Therefore, Conc. Galena \[ \to \] $PbO$ - calcination matching is not correct. Hence, option (C) is incorrect.
The electrolytic reduction is a powerful reduction method, hence it is used for the preparation of pure alumina from red bauxite. And the aluminium oxide is the most stable compound and the Al has more affinity towards oxygen. Therefore, pure aluminum can be prepared from red bauxite by electrolytic reduction method. Thus, Red bauxite \[ \to \] pure Al - electrolytic reduction is correctly matched. Hence, the option (D) is correct.

Note:
Among the given options, copper matte \[ \to \] $Cu$ - self- reduction, Hematite \[ \to \] pig iron - blast furnace and Red bauxite \[ \to \] pure $Al$ - electrolytic reduction is correctly matched. Because, the copper is prepared from copper matte by self -reduction. The pig iron is the intermediate product of iron and the pure aluminum is prepared by using electrolytic reduction. But, the preparation of lead oxide from conc. Galena is not by calcination method.