Marshall's acid (H2S2O8)or peroxodisulphuric acid is prepared by electrolytic oxidation of H2SO4as 2H2SO4=H2S2O8+2H ++2e- O2 and H2obtained as - Chemistry - Electrochemistry

Question

Marshall's acid (H2S2O8)or
peroxodisulphuric acid is prepared by electrolytic oxidation of
H2SO4as 2H​2
SO4=H2S2O8+2H
++2e- O2 and H2obtained
as by product In such electrolysis 4 48L of H2 and 1 12L
of O2 were produced at STP What is The weight of
H2S2O8formed?

Vartika Jain · Accepted Answer

Dear Student,

On the electrolysis of H2S2O8, following changes occurAnode : 2H2SO4 → H2S2O8 + 2H+ + 2e-                  2H2O → 4H+ + O2 + 4e-Cathode: 2H2O + 2e- →2OH- + H2Thus, eq
 wt of H2S2O8 + Eq
 wt of O2=Eq  wt of H2or eq
 wt of H2S2O8=Eq  wt of H2-Eq
 wt of O2=2×4 4822 4-4×1 1222 4=0 4-0
2=0 2(Since, 22
4 L = 1 mole and 1 mole = Eq
 ×valence factor)Therefore, wH2S2O81942=0
2or wH2S2O8=0 2×1942=19 4 g

Marshall's acid (H2S2O8)or peroxodisulphuric acid is prepared by electrolytic oxidation of H2SO4as 2H​2 SO4=H2S2O8+2H ++2e- . O2 and H2obtained as by product . In such electrolysis 4.48L of H2 and 1.12L of O2 were produced at STP. What is The weight of H2S2O8formed?