The role of depressant in froth floatation process is :
1. | To separate two nitrite ores by selectively preventing one ore from forming froth. |
2. | To separate two sulphide ores by selectively preventing one ore from forming froth. |
3. | To separate two sulphide ores by selectively preventing both of them from forming froth. |
4. | To separate two magnesium ores by selectively preventing both of them from forming froth. |
The extraction of copper from pyrites is more difficult than from its oxide ores through reduction because -
1. of HCl is less than that of
2. of HNO3 is less than that of
3. of is less than that of
4. of CuSO4 is less than that of
The correct statement among the following is:
1. | All ores are minerals, but all minerals are not necessarily ores. |
2. | Minerals are an economical source of metal |
3. | Extraction of metal from ores is difficult. |
4. | None of the above |
Leaching of low-grade copper ores does not involve
1. Cu getting converted into Cu2+(aq) in acidic medium
2. Cu getting converted into Cu2+(aq) in basic medium
3. Cu2+(aq) getting reduced to Cu
4. using bacteria in the presence of air.
The process in which Cl2 is obtained as a by-product is :
1. | In the electrolysis of aqueous HCl, Cl2 is obtained at the cathode as a by-product. |
2. | In the electrolysis of aqueous NaCl, Cl2 is obtained at the cathode as a by-product. |
3. | In the electrolysis of molten NaCl, Cl2 is obtained at the anode as a by-product. |
4. | None of the above |
Incorrect statement(s) among the following options is/are:
1. | Roasting is done in a limited supply of air. |
2. | Calcination is done in the absence, or a limited supply of air. |
3. | Roasting is done in a regular supply of air. |
4. | All of the above. |