Question

The reaction that does not define calcination is

• A. $ZnCO _{3} \stackrel{\Delta}{\longrightarrow} ZnO + CO _{2}$
• B. $Fe _{2} O _{3} \cdot XH _{2} O \stackrel{\Delta}{\longrightarrow} Fe _{2} O _{3}+ XH _{2} O$
• C. $CaCO _{3} \cdot MgCO _{3} \stackrel{\Delta}{\longrightarrow} CaO + MgO +2 CO _{2}$
• D. $2 Cu _{2} S +3 O _{2} \stackrel{\Delta}{\longrightarrow} 2 Cu _{2} O +2 SO _{2}$

Answer 1

Answer: (D)

Calcination is a process in which ore is heated mainly in the absence of air whereas roasting is a process in which ore is heated in the presence of air.
$2 Cu _{2} S +3 O _{2} \ce{->[{\Delta}]} 2 Cu _{2} O +2 CO _{2}$ (Roasting)