(i) S–S bond is present in H2S2O6

(ii) In peroxosulphuric acid (H2SO5) sulphur is in +6 oxidation state.

(iii) Iron powder along with Al2O3 and K2O is used as a catalyst in the preparation of NH3 by Haber’s process.

(iv) Change in enthalpy is positive for the preparation of SO3 by catalytic oxidation of SO2

Correct Answers: 

(i) S–S bond is present in H2S2O6

(ii) In peroxosulphuric acid (H2SO5) sulphur is in +6 oxidation state.

Explanation: Iron powder along with Al2O3 and K2O is not used as a catalyst in the preparation of NH3 by Haber’s process and change in enthalpy is negative for the preparation of SO3 by catalytic oxidation of SO2