Extraction of Zinc

Q. The reducing agent used in the reduction of zinc oxide to zinc is:

1. Carbon monoxide
2. Carbon dioxide
3. Pure zinc
4. Coke

Q.

Explain:1. Oxidation method (Oxidative refining) 2. Electrolytic refining [5 MARKS]

Q. Explain extraction of metals.

Q. In the electrolytic refining of Zn, is used as the cathode.

1. crude $Zn$
2. $Al$
3. pure $Zn$
4. $Ca{F}_2$

Q. Zinc blende (ZnS) is concentrated bymethod.

1. magnetic separation
2. froth flotation
3. levigation

Q. Explain Metallurgy process.

Q. Which of the following is not an ore of iron?

1. Magnetite
2. Limonite
3. Bauxite
4. Haematite

Q.

How is zinc obtained from zinc oxide?

Q.

Which of the following refining process is/are used for refining of zinc?

1. Distillation Refining

2. Liquation Refining

3. Oxidation Refining

4. Electrolytic Refining

Q.

State what would you observe when: Barium chloride solution is slowly added to sodium sulphate solution.

Q.

Coke is used in the manufacture of which of the following?

1. Iron

2. Lead

3. Steel

4. Copper

Q.

Which of the following is used as the cathode in electrolytic refining of zinc?

1. Aluminium

2. Pure zinc

3. Impure zinc

4. both pure and impure zinc

Q. Which of the following is not an ore of iron?

1. Haematite
2. Magnetite
3. Bauxite
4. Limonite

Q. Mention ‘C’ and ‘R’ for ores that can be oxidised by calcination and roasting respectively and write the chemical reactions taking place.​

Ore	C/R	Chemical reaction
Bauxite (${\text{Al}}_2{\text{O}}_3.2{\text{H}}_2\text{O}$)
Galena (PbS)​
Magnesite (${\text{MgCO}}_3$)

Q.

Oxides of metals like Ti, Cr and Fe can be reduced by Al in the Aluminothermic process – True or False?

1. True

2. False

Q. Haematite and magnetite are ores of:

1. aluminium
2. zinc
3. iron
4. magnesium

Q. Which of the following processes are widely used in the extraction of moderately reactive metals from their sulphide ore?

1. Electrolytic reduction
2. Heating with carbon
3. Roasting
4. Calcination

Q. Extraction of Zinc from zinc blende is achieved by ___________.

1. electrolytic reduction
2. roasting followed by reduction with carbon
3. roasting followed by reduction with another metal
4. roasting followed by self-reduction

Q. Haematite and magnetite are ores of:

1. aluminium

2. zinc

3. iron

4. magnesium

Q.

Food cans are generally coated with tin rather than zinc because _______.

1. it is more reactive

2. it has a lower melting point

3. it is expensive

4. it is less reactive

Q. In the electrolytic refining of Zn, is used as the cathode.

1. crude $Zn$
2. $Al$
3. pure $Zn$
4. $Ca{F}_2$

Q. Describe the principle involved in each of the following process of metallurgy.
a) Froth Floatation method
b) Electrolytic Refining of Metals
c) Zone refining of Metal

Q. The carbon % in Pig iron ?

Q. State why the iron is not placed at the anode and silver at the cathode during electroplating of iron with silver?

Q. Assertion :In smelting, roasted ore is heated with powdered coke in presence of a flux. Reason: Oxides are reduced to metals by $C$ or $CO$. Impurities are removed as slag.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

Reduction of oxides to elements with carbon generally takes place at high temperature, hence $Al$ is used in an aluminothermic process. It is because:

1. $Al$ is more electropositive than the other metals (to be formed by reduction)
2. Reduction is highly exothermic and heat liberated makes the process spontaneous.
3. $Al$ has maximum affinity for oxygen.
4. Reduction is highly endothermic and heat absorbed makes the process spontaneous.

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Is combustion an oxidation or a reduction process?

Q.

In a mining field, miners found an ore called fool's gold whose chemical formula is ${\text{FeS}}_2$. Which method has to be carried out to convert concentrated ore to its oxide?

1. Calcination

2. Roasting

3. Froth floatation

4. Magnetic separation

Q. The metal which is deposited at the cathode during the electrolysis of the solution of zinc sulphate is :

1. Zn
2. Mg
3. Na
4. H

Q. What is the zinc compound in zinc blende?

1. Zinc bromide
2. Zinc sulphide
3. Zinc chloride
4. none of the above