Baeyer's Process

Q.

What Is The Difference Between Electrochemical Series And Galvanic Series?

Q.

For each substance listed below, explain its significance in the extraction of aluminium:

(a) Bauxite, (b) Sodium hydroxide,

(c) Cryolite, (d) Graphite.

Q. In order to obtain one tonne of aluminium, the following inputs are required:
4 tonnes of bauxite, 150 kg of sodium hydroxide and 600 kg of graphite.
The aluminium compound in bauxite is aluminium oxide and the main impurity is iron (III) oxide. Aluminium is obtained by the electrolysis of aluminium oxide dissolved in cryolite.
(a) When bauxite is treated with sodium hydroxide solution, what happens to:
(i) the aluminium oxide?
(ii) the iron (III) oxide?
(b) (i) Name the process used for the purification of bauxite.
(ii) Write the equation to show the action of heat on aluminium hydroxide.
(c) (i) Write the formula of cryolite.
(ii) Write down the word which correctly completes the following sentence:
"By dissolving aluminium oxide in cryolite, a __________ (conducting/non-conducting) solution is produced.
(iii) Why is so much graphite required for this electrolytic process?
(iv) Write the equation for the reaction which takes place at the cathode.
(d) In construction work, why is the alloy of aluminium, duralumin used rather than pure aluminium.

Q. (a) Give the chemical name and formula of 'cryolite'.
(b) What is the function of cryolite in the extraction of aluminium, other than acting as a solvent for bauxite?

Q. For each of the substances listed below, explain its role in the extraction of aluminium:
(a) bauxite
(b) sodium hydroxide
(c) cryolite
(d) graphite

Q.

In order to obtain 1 tonner of aluminium, the following inputs are required. 4 tonnes of bauxite, 150 kg of sodium hydroxide and 600 kg of graphite. The aluminium compound in bauxite is aluminium oxide and the main impurity is Iron (III) oxide. Aluminium is obtained by the electrolysis of aluminium oxide dissolved in cryolite.

(a) When bauxite is treated with sodium hydroxide solution, what happens to:

(i) the aluminium oxide,

(ii) the iron (III) oxide?

(b) (i) Name the process used for the purification of bauxite.

(ii) Write the equation for the action of heat on aluminium hydroxide.

(c) (i) Write the formulae of cryolite.

(ii) Write down the word which correctly completes the following sentence.By dissolving aluminium oxide in cryolite a ..........(conducting/non conducting) solution is produced.

(iii) Why is so much graphite required for the electrolytic process?

(iv) Write the equation for the reaction which takes palace at cathode.

Q.

Prepare a table showing different minerals and their uses?

Q.

Explain the significance of the following in the extraction of aluminium.
(i) Bauxite
(ii) Sodium hydroxide
(iii) Cryolite
(iv) Graphite

Q.

Which of the following methods is best suited for the concentration of bauxite ore?

1. Hydraulic washing

2. Hydrometallurgy

3. Magnetic separation

4. Leaching

Q.

For the extraction of aluminium answer the following

Why is cryolite mixed with the ore?

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Explain leaching process.

Q.

In Red Bauxite, the major impurity is $Ti{O}_2$ – True or False?

1. True

2. False

Q. What is alumina?
State the uses of aluminium and where iare bauxite deposites found in india

Q. Assertion : Reason: At the positive anode, oxygen gas is formed and at high temperature of the electrolysis cell it burns and oxidises away the carbon electrodes to form toxic carbon monoxide or carbon dioxide.

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.

In Red Bauxite, the major impurity is $Ti{O}_2$ – True or False?

1. True

2. False

Q.

Which one of the following methods is best suited for the concentration of Bauxite ore?

1. Hydraulic washing

2. Hydrometallurgy

3. Magnetic separation

4. Leaching