Extraction of Aluminium

Q.

Purification of aluminum by electrolytic refining is known as ____________________________?

1. Serpecks process

2. Halls process

3. Hoopes process

4. Baeyers process

Q.

Name a compound added to lower the fusion temperature of electrolytic bath in the extraction of aluminium.

Q.

Identify the substance underlined in each of the following:

The electrode that increases in mass during the electro-refining of silver.

Q.

Name the process by which $\mathrm{Al}$ is obtained from purified bauxite.

Q.

The ________ readily adsorbs hydrogen at room temperature.

Q.

Which of the following methods of concentration is inappropriate for an oxide ore?

1. Magnetic separation

2. Froth floatation

3. Gravity separation

4. Chemical separation

Q. One beaker contains 0.15 M $Cd(N{O}_3{)}_2$ and a Cd metal electrode. The other beaker contains 0.20 M $AgN{O}_3$ and a Ag metal electrode. The cell representation of a cell in which cadmium metal oxidizes

1. None of the above.
2. $Cd\left(s\right)|C{d}^{2+}(aq,0.15M)||A{g}^{+}(aq,0.20M)|Ag\left(s\right)$
3. $A{g}^{+}(aq,0.20M)|Ag\left(s\right)||Cd\left(s\right)|C{d}^{2+}(aq,0.15M)$
4. $C{d}^{2+}|Cd\left(s\right)(aq,0.15M)||Ag\left(s\right)|A{g}^{+}(aq,0.20M)$

Q. The sodium is made by electrolysis of a molten mixture of 40% NaCl and 60% $CaC{l}_2$ because :

1. $CaC{l}_2$ helps in the conduction ofelectricity
2. $C{a}^{2+}$ can reduce $NaCI$ to $Na$
3. $C{a}^{2+}$ can displace $Na$ from $NaCI$
4. this mixture has a lower melting point than NaCl

Q. Calcination is a process in which the ore is heated strongly in the absence of air to remove volatile impurities. It thermally decomposes the carbonate.
$A{l}_2{O}_3.2H_{2}O\stackrel{Calcination}{\to }B+2H_{2}O$
The name of product $B$ is:

1. Corundum
2. Bauxite
3. Aluminum hydroxide
4. None of these

Q.

Complete the following

$2A{l}_2{O}_3+3C\to 4A+3B$. A & B are as follows.

1. CO, Al

2. Al, CO

3. Al, CO₂

4. CO₂, Al

Q. In copper pyrites $CuFe{S}_x$, what is the value of $x$?

Q.

What is the formula of diva lent metal chromate?