The number of electrons lost by `2g` of `Cl^(-)` ions during the electrolysis of molten `NaCl` is

Options

A. `3.39 xx 10^(23)`
B. `3.39 xx 10^(20)`
C. `3.39 xx 10^(21)`
D. `3.39 xx 10^(22)`

Answer

D

Explanation

The electrode reaction is
`2Cl^(-)(l) rarr Cl_(2)(g)+2e^(-)`
Number of equivalents of `Ci^(-)` ions discharged
`= ("mass(g)")/("gram equivalent mass" (g eq.^(-1)))`
`= (2g)/(35.5 g eq.^(-1))`
One faraday of electricity (`6.022 xx 10^(23)` electrons) discharges one equivalent of any species. Thus, electrons involved in discharge of `2g` of `CI^(-)` ions is
`(2)/(35.5) xx 6.022 xx 10^(23)`
`= 3.39 xx 10^(22)`