Among the methods for extracting metals from their ores, i.e.,roasting a metal sulphide,chemical reduction of a metal oxide, andelectrolysis, the preferred method depends on E∘ value for the reducing half-reaction:
Mn+(aq)+ne−→M(s)
Which method is preferred for the metals with the most negative E∘ values?
Mn+(aq)+ne−→M(s)
State whether the given statement is True or False.
CuO can't be reduced by carbon but it can be reduced by H_2.
given : \Delta G^{\circ}_{f} for CuO = -129.7 kJ mol^{-1}, CO = - 137.2 kJ mol^{-1} H_2O = - 237.2 kJ mol^{1}
Metal | Ore | Chemical formula | Reduction process |
Al | haemetite | PbS | blast furnace |
Cu | bauxite | Fe_2O_3 | bessemerisation |
Fe | copper pyrite | Al_2O_2H_2O | froth floatation |
Pb | galena | CuFeS_2 | Hall's process |
Ore | Impurity | Method |
High density | Low density | (i) |
Magnetic | Non magnetic | (ii) |
Low density | High density | (iii) |
Dissolved in the solvent | didn't dissolve | (iv) |