Question

The process by which lighter earthy particles are freed from the heavier particles using water is:

• A. Gravity separation
• B. Magnetic separation
• C. Leaching
• D. All of the above

Answer 1

The correct option is A Gravity separation

Gravity separation method is based on differences​ in gravity of ore and gangue particles.
An upward​ stream of running water is used to​ wash the powdered ore where the lighter gangue particles are washed away and heavier ores are left behind.
This method is also know as gravity separation.
Hence, option (a) is correct.

Magnetic separation is used to separate magnetic impurities from non-magnetic ores.

Leaching is a chemical method for concentration of ore.