Question

Electrolysis is carried out for 2.00 h in the following cell. The platinum cathode which has a mass of 25.0782 g, weighs 25.8639g after the electrolysis. The platinum anode weighs the same before and after the electrolysis.
there is H2SO4(aq) on the anode side and AgNO3(aq) on the cathode side.

a) write equations for the half reactions that occur at the two electrodes.

b)what must have been the current used assuming a constant current throughout?

c)a gas is collected at the anode. what is it? how many moles of it are present?

Answer 1

a. Ag^+(aq) + e ==> Ag(s)
4OH^- ==> 4e + 2H2O + O2

b. 25.8639
..-25.0782
mass Ag metal deposited = ?
96,485 coulombs will deposit 107.868 g Ag so
C used = 96,485 x (?g Ag/107.868) = ?coulombs.
C = amperes x seconds.
Substitute and solve for amperes.

c. ?C from above = 96,485 x ?gO2/8
Substitute and solve for ?g O2.