The correct statement s related to the metal extraction processes is(are)

1. A mixture of $\mathrm{PbS}$ and $\mathrm{PbO}$ undergoes self-reduction to produce $\mathrm{Pb}$ and ${\mathrm{SO}}_2.$
2. In the extraction process of copper from copper pyrites, silica is added to produce copper silicate.
3. Partial oxidation of sulphide ore of copper by roasting, followed by self-reduction produces blister copper.
4. In cyanide process, zinc powder is utilized to precipitate gold from $\mathrm{Na}\left[\mathrm{Au}{\left(\mathrm{CN}\right)}_2\right].$

Solution

Asked in: JEE Advanced 2021 (Paper 1)

Practice more General Principles and Processes of Isolation of Metals questions on Aicharya