Question

Consider two chemical reactions $(A)$ and $(B)$ that take place during metallurgical process :
(A) $ZnCO _{3(s)} \xrightarrow{\Delta} ZnO _{(s)}+ CO _{2(g)}$
(B) $2 Z n S_{(s)}+3 O_{2(g)} \longrightarrow 2 Z n O_{(s)}+2 S O_{2(g)}$
The correct option of names given to them respectively is

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

Answer 1

Answer: (A)

(A) $ZnCO _{3}( S ) \xrightarrow{\Delta} ZnO ( s )+ CO _{2}(g)$
Heating in absence of oxygen in calcination.
(B) $2 Zns ( s )+3 O _{2}(g) \rightarrow 2 Zn O (g)+2 SO _{2}(g)$
heating in presence of oxygen in roasting
Hence $(A)$ is calcination while $(B)$ in roasting.