Question

Two electrolytic cells are connected in series, if weight of copper in 1st cell is 6.35gm then find out the weight of Sodium in 2nd cell.


requires explanation.

Answer 1

Answer:

Given,

Moles of Cu=0.4

Number of moles of Al=?

According to Faraday's second law:

moles of Cu = chemical equivalent of Cu

moles of Al. chemical equivalent of Al

Chemical equivalent= atomic weight

valency

For CuSO4

Cu²+2e →Cu

and for AlCl3

Al³ +3e →Al

Thus, Chemical equivalent of Cu = ½

and Chemical equivalent of Al = ⅓

Putting these value in equation (1)

moles of Al 0.4

= 1×2

1×3

moles of Al=

3

0.4×2

=0.266≈0.27 mol