The statement that is $NOT$ correct is:

In the leaching of $Ag_2S$ with $NaCN$,a stream of air is also passed. This is because of:

Which alloy contains a non-metal?

Which of the following statements is not correct?

The electrochemical extraction of aluminum from bauxite ore involves:

The correct statement$(s)$ related to the metal extraction processes is(are):
$(A)$ $A$ mixture of $PbS$ and $PbO$ undergoes self-reduction to produce $Pb$ and $SO_2$.
$(B)$ In the extraction process of copper from copper pyrites,silica is added to produce copper silicate.
$(C)$ Partial oxidation of sulphide ore of copper by roasting,followed by self-reduction produces blister copper.
$(D)$ In the cyanide process,zinc powder is utilized to precipitate gold from $Na[Au(CN)_2]$.