Question

Which of the following is used as an electrolyte for antimony Plating?

(a) KNO3

(b) Dilute H2SO4

(c) Silver in potassium solution

(d) HCl

The question was posed to me in an interview.

Origin of the question is Electroplating Baths in portion Electroplating of Engineering Chemistry II

Answer 1

The correct choice is (c) Silver in potassium solution

To explain I would say: Usually in the antimony plating method, the pure antimony bar acts as the anode, the object is to be plated (impure metal) acts as the cathode and the silver in potassium solution acts as the electrolyte. When electricity is passed between the electrodes, the positive silver ions from the electrolyte move to the negative anode (the object), where they are neutralized by the electrons and adhere to the object as silver. On further transmission we get antimony deposition.