Science Define :

It is a process in which magnetic ore is separated from non magnetic impurities with the help of electromagnetic machines.

This process is used to concentrate some ores especially sulphide ores. In this process, the finely powdered ore is mixed with water and a suitable oil, like pine oil. It is based on the principle that the mineral particles due to their hydrophobic property are wetted with oil, whereas gangue particles get wetted with water due to the hydrophilic property.

It is the process in which finely grounded (powdered) ore is washed with a stream of water. The lighter gangue particles are washed away in a stream of water whereas heavier mineral particles settle down at the bottom. It is based on difference in the density of ore and impurities.

Compounds formed from two units namely cation and an anion are called Ionic compounds.

An alloy is the homogeneous mixture formed by mixing a metal with other metals or non- metals in certain proportion.

The process of giving a protective coating of tin over other metals is called tinning.

The process where metals like copper and aluminium are coated with a thin and strong layer of their own oxides by means of electrolysis is called anodizing.

The process where a less reactive metal is coated on a more reactive metal using electrolysis is called electroplating.

Galvanizing is a process of giving a thin coating of zinc on iron or steel to protect them from corrosion.

The conversion of metal oxide into metal is called reduction.

The process of conversion of carbonate ores into oxides by strongly heating in limited supply of air is called calcination.

The process of conversion of sulphide ores into oxide by strongly heating in air is called roasting.

The science and technology regarding the extraction of metals from ores and their purification for the use is called metallurgy.

Ores contain metal compounds with some of the impurities like soil, sand, rocky substances etc. These impurities are called gangue.

The minerals from which the metals can be separated economically are called ores.

The compounds of metals that occur in nature along with the impurities are called minerals.