Question

explain roasting and calcination ​

Answer 1

$\huge{\underline{\tt{Roasting:-}}}$

❥Roasting is the process in which the ore is heated below its melting point in presence of air to oxidise the impurities.

$\huge{\underline{\tt{Calcination:-}}}$

❥ Calcination is the process of heating the ore below its melting point an absence of air to remove volatile impurities like arsenic .

Answer 2

Answer:

Roasting

1.One is heated in the presence of excess of oxygen or air.

2.This method is employed for sulphide ores.

3.Sulphur dioxide is produced along with metal oxide.

4.Example: For the ores ZnS (sphalerite) and Cu2S (chalcocite), balanced equations for the roasting are:

2ZnS+3O2-->2 Zno+ 2SO2

2 Cu2S + 3O2 → 2 Cu2O + 2 SO2

Answer:

Calcination

1.one is heated in the absence or limited supply of oxygen or air.

2.This method is employed for carbonate ores.

3.Carbon dioxide is produced along with metal oxide.

4.Example: ZnCO3--> ZnO+ C02.