Extraction of Metals

Q. Silver and gold occur in the free state in nature state reason for the following ?

Q. Which of the following ores can be concentrated by magnetic separation?

1. 
   Pyrolusite (${\mathrm{MnO}}_2$)
2. 
   Cassiterite (${\mathrm{SnO}}_2$)
   
3. 
   Chromite (${\mathrm{FeCr}}_2{O}_4$)
   

Q. The highly reactive metals like sodium, potassium, magnesium etc are extracted by:

1. $\text{Electrolysis of their molten Chloride}$
2. $\text{Electrolysis of their molten Oxide}$
3. $\text{Reduction by Aluminium}$
4. $\text{Reduction by Carbon}$

Q.

What is metal reactivity series?

Q.

In nature, aluminium is found in the form of compounds while gold is found in the free state. Give reason.

Q. Define the terms:
(i) mineral
(ii) ore
(iii) gangue
(iv) charge
(v) flux
(vi) slag

Q. Which of the following metals are available in nature in a free state?

1. Gold
2. Silver
3. Sodium
4. Calcium

Q. The impurities present in mined ores are technically calledand the process of removing them from the ore is calledof an ore.

1. gangue
2. flux
3. concentration
4. metallurgy

Q.

The impurities that are associated with the ore are called ?

Q.

Which of the following can be used as a reducing agent in smelting?

1. Carbon

2. Coke

3. Carbon monoxide

4. All of the above

Q.

What type of chemical reaction is used to extract metals from their naturally occurring compounds like oxides or chlorides ?

Q.

Name the process of extracting pure metal from their ores.

Q.

Mention the names of the steps in metallurgy.

Q.

Potassium is never found in nature as free element because:

1. Potassium is present at the top of the activity series.

2. Potassium is present at the bottom of the activity series.

3. Potassium is present in the middle of the activity series.

4. Potassium is an unreactive metal

Q.

Silver is found in nature as a free element as well as compounds because:

1. Silver is highly reactive metal.

2. Silver is present at the top of the activity series.

3. Silver is present at the bottom of the activity series.

4. Silver is present in the middle of the activity series.

Q. Haematite can be concentrated by magnetic separation.

1. False
2. True

Q.

Magnesium is the most abundant metal in the Earths crust.

1. True
2. False

Q.

In nature, aluminium is found in the form of compounds while gold is found in free state. Give reason.

Q. Statement 1: It is easier to extract the metals that are present at the top of the reactivity series.
Statement 2: Metals at the top of the reactivity series are highly reactive in comparison with the metals at the bottom.

1. Both statements are true.
2. Both statements are false.
3. Only statement 1 is true.
4. Only statement 2 is true.

Q. 2Na+Cl2 gives 2NaCl
Here addition of electropositive element(Na)
And addition of electronegative element(Cl)
Takes place. Is this a redox reaction

Q.

Explain the following term: Metallurgy

Q. How are the less reactive metals extracted?

Q.

The metals which are generally found in the free state are generally present _______ the activity series.

1. at the top of

2. in the middle of

3. above hydrogen in

4. at the bottom of

Q. Gravity separation technique is used when the ore and impurities have different specific gravities.

1. True
2. False

Q. Which among these options use the froth floatation process?

1. Chalcopyrite
2. Bauxite
3. Haematite
4. Calamine

Q. Iron ore is concentrated by the process of smelting.

1. True
2. False

Q.

which of the following is an example of metal?

Q. The material that is mixed before the ore is subjected to smelting in the extraction of iron is

1. limestone and silica
2. coke and silica
3. coke and limestone
4. coke, limestone, and silica

Q.

Zone refining is based on the principle of that the impurities tend to be in the melt than in the solid metal.

1. False

2. True

Q. A non-metal $‘X^{\prime }$ is present in the atmosphere in the form of a diatomic gaseous molecule and in air, its proportion is $78\%$, $‘X^{\prime }$ is

1. oxygen
2. hydrogen
3. chlorine
4. nitrogen