Question

differentiate between roasting and calcination with two chemical equations how is zinc extracted from its ore

Answer 1

Roasting

1)The ore is heated in the excess of air.

2)Generally sulphide ores are roasted so So2 is given off.

3)2ZnS+3O2 gives ZnO+2So2 on 800°--900°

3)Volatile impurities are removed as oxides So2 P2O5)and ores become porous and more reactive.

Calcination

1)The ore is heated in the absence of air.

2)Carbonate and hydrated ores are calcined and Co2 or water vapours are given off.

ZnCo3 gives Zno+ Co2

3)Moisture and organic impurities are removed and the ore become porous and more reactive.

I hope this answer would help you .

Thankyou so much friend for your points