The compound(s) having peroxide linkage is(are)
- H2S2O7
- H2S2O8
- H2S2O5
- H2SO5
Answer
(2) H2S2O8, (4) H2SO5
Solution
H2S2O7 (pyrosulphuric acid): HO₃S–O–SO₃H, S–O–S bridge, no O–O.
H2S2O8 (peroxodisulphuric acid): HO₃S–O–O–SO₃H → peroxide linkage.
H2S2O5 (pyrosulphurous acid): HO–S(O)–S(O)₂–OH, S–S bond, no O–O.
H2SO5 (Caro’s acid, peroxomonosulphuric acid): HO–O–SO₂–OH → peroxide linkage.
Answer: (B), (D)