Blister $Cu$ contains approximately ....... $\%$ $Cu$.

Observe the following statements:
Statement-$I$: The choice of reducing agent for the reduction of an oxide ore can be predicted by using Ellingham diagram,a plot of $\Delta G^{\ominus}$ vs $T$.
Statement-$II$: According to Ellingham diagram,metal oxide with higher $\Delta G^{\ominus}$ is more stable than the oxide with lower $\Delta G^{\ominus}$.

The carbon-based reduction method is $NOT$ used for the extraction of:

Which of the following reactions takes place during the smelting process?

The reaction occurring in the final stage of the extraction of copper from copper pyrites in a Bessemer converter is:

Which among the following is used as flux in the extraction of iron from oxide ores?