Extraction of Copper

Q.

Question 6

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified permanganate solution. The light purple colour of the solution fades and finally disappears.

Which of the following is the correct explanation for the observation?

(a) ${\text{KMnO}}_4$ is an oxidizing agent, it oxidises ${\text{FeSO}}_4$.
(b) ${\text{FeSO}}_4$ acts as an oxidizing agent and oxidises ${\text{KMnO}}_4$.
(c) The colour disappears due to dilution; no reaction is involved.
(d) ${\text{KMnO}}_4$ is an unstable compound and decomposes in presence of ${\text{FeSO}}_4$ to a colourless compound.

Q.

Among the statements (a)-(d), the correct ones are:

(a) Limestone is decomposed to $\mathrm{CaO}$ during the extraction of iron from its oxides.

(b) In the extraction of silver, silver is extracted as an anionic complex.

(c) Nickel is purified by Mond’s process.

(d) $\mathrm{Zr}$ and $\mathrm{Ti}$ are purified by Van Arkel method.

1. $\left(\mathrm{c}\right)$ and $\left(\mathrm{d}\right)$ only

2. $\left(\mathrm{b}\right),\left(\mathrm{c}\right)$ and $\left(\mathrm{d}\right)$

3. $\left(\mathrm{a}\right),\left(\mathrm{b}\right),\left(\mathrm{c}\right)$ and $\left(\mathrm{d}\right)$

4. $\left(\mathrm{a}\right),\left(\mathrm{c}\right)$ and $\left(\mathrm{d}\right)$

Q.

Match List-1 with List-2

Column 1	Column 2
Aluminum	Siderite
Iron	Calamine
Copper	Kaolinite
Zinc	Malachite

Q.

The oxidation state of Cu and Fe in $CuFe{S}_2$ are ___ and___respectively

Q.

What happens during the process of smelting of iron?

1. The weight of the iron produced is lower than the weight of the iron ore used.

2. The weight of the iron produced is greater than the weight of the iron ore used.

3. The weight of the iron produced is equal to the weight of the iron ore used.

4. The weight of iron produced cannot be determined

Q. Stainless steel is an example of a _______.

1. compound
2. heterogeneous mixture
3. colloid
4. homogeneous mixture

Q.

The main ore used for the extraction of iron is

1. haematite

2. calamine

3. bauxite

4. cryolite

Q. What type of a substance is steel?

1. A solid-liquid heterogeneous mixture
2. A solid-liquid homogeneous mixture
3. A solid-solid homogeneous mixture
4. A pure substance

Q. Which ore contains both iron and copper?

1. Cuprite
2. Chalcocite
3. Chalcopyrite
4. Malachite

Q.

Which of the following is the correct statement for red lead

1. It is an active form of lead

2. Its molecular formula is Pb₂O₃

3. It decomposes into Pb and CO₂

4. It decomposes into PbO and O₂

Q. Upon heating with $C{u}_{2}S$, the reagents that give copper metal is/are

1. $CuFe{S}_2$
2. $CuO$
3. $C{u}_{2}O$
4. $CuS{O}_4$

Q. If steel is heated bright red hot, and is then cooled slowly, the process is called:

1. quenching
2. annealing
3. tempering
4. smelting

Q.

Oh! We are nearly there. You can almost smell copper. Molten Copper Matte is then transferred to a Bessemer converter where it undergoes___reduction

Q. Although there are several ores, 80% of the world copper production comes from the ore chalcopyrite ($CuFe{S}_2$). The extraction of copper from chalcopyrite involves partial roasting, removal of iron and self-reduction. Partial roasting of chalcopyrite produces:

1. $CuS$ and $F{e}_2{O}_3$
2. $C{u}_{2}S$ and $FeO$
3. $C{u}_{2}O$ and $FeO$
4. $C{u}_{2}O$ and $F{e}_2{O}_3$

Q. The chemical composition of slag formed during the smelting process in the extraction of copper is
(IIT-JEE, 2001)

1. $C{u}_{2}O+FeS$
2. $FeSi{O}_3$
3. $CuFe{S}_2$
4. $C{u}_{2}S+FeO$

Q. Extraction of copper from copper pyrite $CuFe{S}_2$ involves

1. Crushing followed by concentration of the ore by froth-floatation
2. Removal of Iron as slag
3. Self-reduction step to produce 'blister copper' following evolution of $S{O}_2$
4. Refining of 'blister copper' by carbon reduction

Q.

Oh! We are nearly there. You can almost smell copper. Molten Copper Matte is then transferred to a Bessemer converter where it undergoes___reduction