Question

Removal of unwanted materials like sand, clays, etc from the ore is known as ______, _______ or _______.
A.concentration, dressing,benefaction
B.separation, refining, gangue
C.magnetic separation, purification, gangue
D.washing, refining, amalgamation

Answer 1

Hint: We know that metallurgy is the entire process in which scientific technology is used to isolate metal from its ore. Out of all minerals, ore is the mineral which is the source of the particular metal.

Complete step by step answer:
Let's first understand mineral and ore in detail.
Minerals are the naturally occurring substances present in Earth's crust. All minerals are not ores. Only some of the minerals are used as a source of the particular metal. These minerals are known as ores.
An ore is contaminated with many undesired earthly substances. These undesired substances are known as gangue. The process of removing unwanted materials such as clay, sand etc. from the ore is termed as concentration, benefaction or dressing. This process involves many steps. The removal of the gangue depends on the physical properties of the gangue and the metal.

So, the correct answer is Option A.

Additional Information:
Some of the important procedures of concentration of ores are hydraulic washing, froth floatation method, magnetic separation etc.

Hydraulic washing is the process in which the separation of the gangue and the ore is based on the difference in gravities of both. Therefore, it is a type of gravity separation.

Magnetic separation is the process in which the separation of gangue and the ore is based on difference in magnetic properties. If any one of the components is attracted by magnet, then the separation is done by this method.

Note: Always remember that extraction and isolation of metals from ores involves three main steps, 1st is concentration of ore, 2nd is isolation of metal from its ore and third step is purification of the metal.Some of the important procedures of concentration of ores are hydraulic washing, froth floatation method, magnetic separation etc.

Hydraulic washing is the process in which the separation of the gangue and the ore is based on the difference in gravities of both. Therefore, it is a type of gravity separation.
Magnetic separation is the process in which the separation of gangue and the ore is based on difference in magnetic properties. If any one of the components is attracted by magnet, then the separation is done by this method.