Extraction of Highly Reactive Metals

Q. Why calcium floats over water during the reaction with water

Q. Which among the following is true, when calcium is treated with cold water?

1. Calcium does not react with cold water.
2. Hydrogen gas evolved catches fire.
3. Hydrogen gas evolved does not catch fire.
4. Calcium floats on the surface of the water.

Q.

When metal burns and reacts to oxygen, is it endothermic or exothermic?why?

Q.

Electrolysis involves oxidation and reduction respectively at:

1. Anode, Cathode

2. Cathode, Cathode

3. Cathode, Anode

4. Anode, Anode

Q. A company finds smithsonite (ZnC$O_3$) in a digging area. Identify the final stage to extract the metal.

1. Reduction using coke
2. Refining of Zn
3. Roasting
4. Electrolytic reduction

Q. Based on the activity series, which of the following elements can be extracted by the process of electrolysis?

1. Calcium
2. Copper
3. Zinc
4. Gold

Q. A metal which exists as a liquid at room temperature is obtained by heating its sulphide ore in the presence of air.
(a) Name the metal and write its chemical symbol.
(b) Write the name and formula of the sulphide ore.
(c) Give the equations of chemical reactions involved in the production of metal from its sulphide ore.
(d) Name a common device in which this metal is used.
(e) Can this metal displace copper from copper sulphate solution? Why?

Q. The general process flow in metallurgy of zinc blende is:

1. Mining
2. Froth flotation
3. Roasting
4. Reduction
5. Refining

Q. Based on activity series, which of the following elements can be extracted by the process of electrolysis?

1. Calcium
2. Copper
3. Zinc
4. Gold

Q. Which of the following metals can be found in its free state?​

Q. Different techniques are used for obtaining the metals falling in each category. The metals high up in the reactivity series are obtained by:

1. reduction with carbon
2. electrolytic reduction
3. reduction by heating
4. displacement reaction

Q. Based on the activity series, which of the following elements can be extracted by the process of electrolysis?

1. Calcium
2. Copper
3. Zinc
4. Gold

Q.

A metal which is highly reactive can't exist in the native state.

1. False

2. True

Q. Aluminium can be obtained by the electrolytic refining of aluminium oxide.

1. False
2. True

Q. Metals form coloured salts are

1. Transition metals
2. all metals
3. non-metals
4. p-block elements

Q. Based on the activity series, which of the following elements can be extracted by the process of electrolysis?

1. Calcium
2. Copper
3. Zinc
4. Gold

Q. Assertion: The impurities such as ${\text{SiO}}_2$ present in iron ore is removed by ${\text{CaCO}}_3$.

Reason: $\text{CaO}$ formed by decomposition of ${\text{CaCO}}_3$ reacts with ${\text{SiO}}_2$ to form slag.

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

Q. Metals at the top of the reactivity series $K,Na,Ca$ are never found in nature as free elements.

1. True
2. False

Q. Based on activity series, which of the following elements can be extracted by the process of electrolysis?

1. Zinc
2. Gold
3. Calcium
4. Copper

Q. Which of the following reactions are examples of calcination?

1. ${\mathrm{CaCO}}_3\left(s\right)\to \mathrm{CaO}\left(s\right)+{\mathrm{CO}}_2\left(g\right)$

2. $4{\mathrm{FeS}}_2\left(s\right)+11O_2\left(g\right)\to 2{\mathrm{Fe}}_2{O}_3\left(s\right)+8{\mathrm{SO}}_2\left(g\right)$

3. $$ 2\mathrm{Al}{\left(\mathrm{OH}\right)}_3\left(s\right)\to {\mathrm{Al}}_2{O}_3\left(s\right)+3H_{2}O\left(g\right)$\left(\right)$

4. $$ \mathrm{CuS}\left(s\right)+{\mathrm{CuSO}}_4\left(\mathrm{aq}\right)\to 2\mathrm{Cu}\left(s\right)+2{\mathrm{SO}}_2\left(g\right)$\left(\right)$

Q. Highly reactive metals like sodium and potassium are extracted from their ore by the process of:

1. roasting
2. reduction of metal oxide
3. electrolytic reduction
4. calcination

Q. Which of these can be used to extract a metal from its oxide?

1. More reactive metal
2. Carbon
3. Oxidizing agent
4. Reducing agent

Q.

A metal which is highly reactive can't exist in the native state.

1. False

2. True

Q. It is easier to extract least reactive metals like gold and platinum.

1. True
2. False