Froth flotation process is used for the concentration of:

The methods $NOT$ involved in the concentration of ore are:
$A$. Liquation
$B$. Leaching
$C$. Electrolysis
$D$. Hydraulic washing
$E$. Froth flotation
Choose the correct answer from the options given below:

Observe the following statements regarding the purification of bauxite:
$I$. During Hall's process,silica is removed as $Si$ (vapour).
$II$. Bauxite ore contaminated with $Fe_2O_3$ is purified in Baeyer's process.
$III$. During Serpeck's process,$AlN$ is formed.
The correct answer is:

In the concentration of $PbS$ containing $ZnS$ as impurity,the depressant used is:

$A$ substance which reacts with gangue to form fusible material is called:

The ore that is concentrated by the froth floatation process is