Question

Which of the following compounds would you expect to have to undergo electrolysis to obtain free metals? explain your choice.

a. KCl b. Ag₂O c. Fe₂O₃

Answer 1

best choice : KCl

explanation:

in general electrolytic reduction method is used to reduce metal which are having high electropositivity. here K+ ion high electropositive element so there is no reducing agent is suitable for reduce K+ so it is suitable method is electrolytic reduction.

molten KCl when electrolysed it gives K metal at cathode and Cl2 at anode.

KCl -----------------> K+ + Cl-

cathode : K+ + e- -------------------> K (s)

anode: 2 Cl- -----------------> Cl2 (g)

Ag2O also reduced in the electrolysis but we need not use electrolysis for this

Fe2O3 can be reduced by coke

Fe2O3 + 3C----------------> 2Fe + 3CO