Question

Consider two chemical reactions (A) and (B) that take place during metallurgical process :

$\text{(A)}ZnC{O}_{3\left(s\right)}\stackrel{\Delta }{⟶}Zn{O}_{\left(s\right)}+C{O}_{2\left(g\right)}$

$\text{(B)}2Zn{S}_{\left(s\right)}+3O_{2\left(g\right)}\stackrel{\Delta }{⟶}2Zn{O}_{\left(s\right)}+2S{O}_{2\left(g\right)}$

• A. Both (A) and (B) are producing same product so both are roasting
• B. (A) is roasting and (B) is calcination
• C. Both (A) and (B) are producing same product so both are calcination
• D. (A) is calcination and (B) is roasting

Answer 1

The correct option is D (A) is calcination and (B) is roasting

In calcination, the ore is heated at high temperature in absence of air/limited supply of air.
In roasting, the concentrated ore is heated at high temperature below the melting point of the metal in excess of air. This reaction occurs in reverberatory furnace.
A is calcination since ore is heated at limited supply of air, B is roasting since ore is heated in excess of air.
Option (b) is correct