Electrochemistry - Result Question 18
####19. 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
[2020]
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Solution:
- (d) 1 equivalent of any substance is deposited by $1 F$ of charge.
$20 g$ calcium contains,
Number of equivalents $=\frac{\text{ Given mass }}{\text{ Equivalent mass }}$
(Equivalent mass of $Ca$
$ .=\frac{\text{ Atomic mass }}{\text{ Valency }}=\frac{40}{2}=20) $
$ =\frac{20}{20}=1 $
So, 1 Faraday of charge is required to deposit 1 equivalent of $Ca$.
