\((i) Zr + 2I_2 \xrightarrow{870K} ZrI_4 \xrightarrow{2075K} Zr + 2I_2 \)
\((ii) Ni + 4CO \xrightarrow{330K} Ni(CO)_4 \xrightarrow{450K} \underset{(pure)}{Ni} + 4CO \)
The processes (ii) and (i) above, respectively, are :
1. Mond's process; Van Arkel process
2. Van Arkel process; Mond's process
3. Goldschmidt process; Mond's process
4. Mond's process; Goldschmidt process
Which metal can be purified by zone refining?
1. Ni
2. Zr
3. In
4. Fe
Pb and Sn are extracted from their chief ore by:
1. carbon reduction and self-reduction respectively.
2. self-reduction and carbon reduction respectively.
3. electrolysis and self-reduction respectively.
4. self-reduction and self-reduction respectively.
The correct statement among the following is:
| 1. | The rate of reaction cannot be understood from the Ellingham diagram. |
| 2. | During the formation of metal oxide \(\Delta S\) becomes negative and \(\Delta G\) becomes positive resulting in a positive slope. |
| 3. | There is an abrupt change in the slope of the Ellingham line when a change in phase (s→l) or (l→g) takes place. |
| 4. | All of the above. |
Identify the incorrect statement:
| 1. | The scientific and technological process used for isolation of the metal from its ore is known as metallurgy |
| 2. | Minerals are naturally occurring chemical substances in the earth's crust |
| 3. | Ores are minerals that may contain a metal |
| 4. | Gangue is an ore contaminated with undesired materials |
The fundamental principle of froth flotation process is:
| 1. | Impurities and metal ore have different wetting properties. |
| 2. | Impurities and metal ore have different solubility. |
| 3. | Impurities and metal ore have different diversity. |
| 4. | Impurities and metal ore have different compressive powers. |
Identify incorrect match -
1.
2.
3.
4.
Which among the following is not an oxide ore?
1. Malachite
2. Cuprite
3. Zincite
4. Bauxite
Mg in the Kroll process acts as
(1) Reducing agent
(2) Oxidizing agent
(3) Oxidizing agent at low temperature
(4) Reducing agent at low temperature
The process of converting hydrated alumina into anhydrous alumina is called
1. Roasting
2. Smelting
3. Dressing
4. Calcination