One faraday of electricity will liberate one gram-atom of the metal form a
solution of
(a)aucl3 (b) bacl2 (c) cuso4 (d) nacl

D) NaCl

Explanation: In given answer choices the metals are Au, Ba, Cu and Na. Cl has -1 charge and sulfate ion has -2 charge.

Since there are three Cl atoms for each Au, the charge on Au is +3. Similarly, the charge on Ba is +2, charge on Na is +1. There is one sulfate ion for each Cu and so the charge on Cu is +2.

In electrolysis, the metals are deposited when they are reduced on accepting electrons. The half equations for all the above four metals are written as:

Looking at all the four equations, it's only the last equation that involves one electron. So, one faraday of electricity will liberate one gram-atom of sodium metal from a solution of NaCl.

it's filtration, but this is an assumption so my apologies if i got this