How many faradays of electricity are required to deposit 10g of calcium from molten calcium chloide using inert electrodes ?
(Molar mass of calcium =40 g `mol^(-1)`)

Options

A. `0.5 F`
B. `1 F`
C. `0.25 F`
D. `2F`

Answer

A

Explanation

Relatonship obtained on combing faraday 's first and second laws
`W=ZQ=(E )/(F)xxxQ=(Q)/(F)xx(E )=(Q)/(F)xx(M)/(Z)`
`=(Ixxt)/(F)xx(M)/(Z)`
Here Z= electrochemical equivalent
Q = quantity of electricity passed
E= equivalent mass
M=atomic mass
Z= valency of the metal
F = one faraday or 986500 C
given weight of calcium that has to e deposited = 10 g z of the metal ion =2
molecular mass of calcuiu `=40 g "mol"^(-1)`
`W=(I.T)/(F)xx(M)/(Z), 10 =(I.T)/(F)xx(40)/(2)`
`(10xx2)/(40)` F=IT `rarr` 0.5 F = I.T
0.5 F of electricity is required to deposit 10 g of calcium from molten calcium chloiride usieng inert electrodes