Extraction of Copper

Q.

Explain the average oxidation state of ${\mathrm{Fe}}_3{\mathrm{O}}_4$.

Q.
The common impurities present in bauxite ore are ________

1. $F{e}_2{O}_3\text{and}CuO$
2. $F{e}_2{O}_3\text{and}PbO$
3. $Ti{O}_2\text{and}Si{O}_2$
4. $Si{O}_2\text{and}CuO$

Q. Crude sodium chloride obtained by crystallisation of brine solution does not contain

1. $N{a}_{2}S{O}_4$
2. $MgS{O}_4$
3. $CaS{O}_4$
4. $MgC{l}_2$

Q. The slag obtained during the extraction of copper from copper pyrites is composed mainly of

1. $CaSi{O}_3$
2. $FeSi{O}_3$
3. $CuSi{O}_3$
4. $Si{O}_2$

Q.

Explain Electrolytic Refining Of Metals.

Q.

Blister copper is :

1. Electrically refined copper

2. A mixture of impure copper and silver

3. Copper containing 2% impurity

4. Present in the anode mud in an electrolytic process

Q.

What is the chemical formula of Siderite?

Q.

State the role of silica in the metallurgy of copper .

Q. Given below are two statements.

$\text{Statement-I:}$ During electrolytic refining, blister copper deposits precious metals.

$\text{Statement-II:}$ In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.

In the light of the above statements, choose the correct answer from the options given below.

1. $\text{Statement-I}$ is true but $\text{Statement-II}$ is false.
2. Both $\text{Statement-I}$ and $\text{Statement-II}$ are false
3. $\text{Statement-I}$ is false but $\text{Statement-II}$ is true
4. Both $\text{Statement-I}$ and $\text{Statement-II}$ are true.

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

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

Q. 2.5 Faradays of electricity is passed through a solution of $CuS{O}_4$ The number of gram equivalents of copper deposited on the cathode will be

1. 1
2. 2
3. 2.5
4. 1.25

Q.

Can 1M $NiS{O}_4$ be stored in a vessel of copper? Given that $E_{\frac{{Ni}_{2+}}{Ni}}^0$ = -1.20 V and E°Cu2+/Cu =0.34V

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. Cu is obtained by self reduction.?how

Q.

How is $\mathrm{FeO}$ removed during the extraction of Copper?

Q.

Why is the extraction of copper from pyrites more difficult than that from its oxide ore through reduction?

Q.

What is the purpose of Electrorefining?

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. What is the chemical composition of 'slag' formed during smelting in the extraction of copper?

1. $C{u}_{2}Si{O}_3$
2. $FeSi{O}_3$
3. $CuSi{O}_3$
4. $CuFe{S}_2$

Q.

What contains anode mud?

Q. What is the chemical formula of iron ore Hematite?
(correct answer +1, wrong answer -0.25)

1. $F{e}_2{O}_3$
2. $F{e}_{2}O$
3. $F{e}_3{O}_4$
4. $Fe{S}_2$

Q. Calcination is the process of heating the ore:

1. 
   In inert gas
2. 
   In the presence of air
3. 
   In the absence of air
4. 
   In the presence of $CaO$ and $MgO$

Q.

Silver ore is related with NaCN (aq) to

A.)reduce metal

B.)extract pure silver

C.)refine silver

D.)to remove the impurities

Q.

The number of electrons involved in the electro deposition of 63.5g of Cu from a solution of CuSO4 is

1)6.0×10(23) 2)3.011 ×10(23). 3)12.04×10(23) 4)6.02×10(22) (the ones in the brackets the powers)

Q.

The process of removing lighter gangue particles by washing in a current of water is called

1. levigation

2. liquation

3. leaching

4. cupellation

Q. Which of the following statements is incorrect about the extractive metallurgy of copper?

1. Matte formed after smelting chiefly consists of cuprous sulfide and a bit of ferrous sulfide.
2. Most of the $Si{O}_2$ impurity is removed as fusible slag during roasting which combines with flux FeO.
3. The copper pyrites are concentrated by the froth floatation process.
4. FeS as an impurity is roasted to FeO which reacts with flux $Si{O}_2$ to form slag $FeSi{O}_3$ in the blast furnace during smelting and in a Bessemer Converter during self reduction.

Q. What is the composition of 'Copper matte'?

Q. Which of the following is an acidic flux?

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

Q.

How is Copper separated?

Q.

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