Extraction of Copper

Q.

Which metal is obtained by Self Reduction Process?

Q.

$\mathrm{Pb}$ and $\mathrm{Sn}$ are extracted from their chief ore by?

1. self reduction and electrolysis respectively

2. electrolysis and self reduction respectively

3. carbon reduction and self reduction respectively

4. self reduction and carbon reduction respectively

Q.

Explain the following in terms of gain of oxygen with two examples each. Reduction

Q.

Metal oxide, sulphur dioxide and oxygen are formed on the decomposition of

1. Metal carbonates.

2. Metal sulphates.

3. Metal nitrates.

4. Metal chlorates.

Q.

Complete the following statements by choosing the correct type of reaction for x and y.

Statement 1. The heating of ammonium dichromate is an example of ‘x’ reaction

Statement 2. The heating of zinc oxide with coke is an example of ‘y’ reaction.

1. 

2. 

3. 

4. 

Q.

Which one of the following figures correctly describes the process of electrolytic refining?

1. 

2. 

3. 

4. 

Q.

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

Q. During the process of electrolytic refining of copper, some metals present as impurity settle as anode mud. These are-

1. $PbandZn$
2. $SnandAg$
3. $FeandNi$
4. $AgandAu$

Q.

Which of the following is not an ore of copper?

1. Azurite

2. Karnallite

3. Chalcopyrite

4. Covellite

Q. The correct formula of Zeise’s salt is

1. $[PtC{l}_3.C_2{H}_6{]}^{-}{K}^{+}$
2. $[PtC{l}_2.(C_2{H}_2{)}_2{]}^{-}{K}^{+}$
3. $K^{+}[PtC{l}_3.C_2{H}_4{]}^{-}$
4. $[PtC{l}_3.C_6{H}_6]$

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. Iron is removed from chalcopyrite as:

1. $FeO$
2. $FeS$
3. $F{e}_2{O}_3$
4. $FeSi{O}_3$

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. 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.

When copper pyrite is roasted in excess of air, a mixture of $C{u}_{2}S$ and $FeO$ are formed. FeO is present as impurity. This can be removed as slag during Smelting. The flux added to form slag is

1. Silica which is an acidic flux

2. Limestone, which is a basic flux

3. $Si{O}_2$ which is a basic flux

4. CaO which is a basic flux

Q.

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

Q. Copper is purified by electrolytic refining of blister copper. The correct statement(s) about this process is (are):

1. Impure $Cu$ strip is used as cathode
2. Acidified aqueous $CuS{O}_4$ is used as electrolyte
3. Pure $Cu$ deposits at cathode
4. Impurities settle as anode-mud

Q.

While your siblings are eagerly anticipating their first batches of Gold and diamond, you are still yet to get a single gram of copper! Armed with the know-how of extracting copper, you smelt the calcine from the roasting process in a blast furnace. What is the smelt composed of?

1. Pure Cu metal

2. Crude Cu metal

3. $C{u}_{2}S$ and FeS

4. Matte Copper

Q.

Metal oxide, sulphur dioxide and oxygen are formed on the decomposition of

1. metal carbonates

2. metal sulphates

3. metal nitrates

4. metal chlorides

Q.

In a sad twist you inherit “only” a copper mine while your siblings inherit gold and diamond mines. On inspection you come to know that your copper mine is fully equipped to extract the metal from the ore and also that it consists only of Chalcopyrite. Finely powdered, pulverized ore is ready to be processed. What would be your next step?

1. Concentration using froth floatation

2. Smelting

3. Refining

4. Roasting

Q.

Given below are the steps for the extraction of copper from its ore. Write the reaction involved.

Reduction of copper (I) oxide with copper (I) sulphide.

Q. Which of the following is an acidic flux?

1. $CaO$
2. $MgO$
3. $Si{O}_2$
4. All of these