Q. The number of Faradays(F) required to produce 20 g of calcium from molten $CaCl_2$ (Atomic mass of Ca = 40 g $mol^{-1}$) is :
A) 2
B) 3
C) 4
D) 1
Explanation
[Solution] 20 g Ca = 0.5 mol; $Ca^{2+} + 2e^- \rightarrow Ca$ needs 2 × 0.5 = 1 F. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.