Which of the following set is having correct statements?
$1.$ ${\mathrm{H}}_2{\mathrm{O}}_2$ is a weak base
$\text{2}\text{.}{\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$ oxidizes Fe (II) to Fe (III)
$3.$ ${\mathrm{H}}_2{\mathrm{O}}_2$ can be obtained by the electrolysis of conc. ${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$
$\text{4}\text{.}{\text{H}}_{\text{2}}{\text{O}}_{\text{2}}$ reduces Mn (VII) to Mn (II)

• A

  2, 3
• B

  3, 4
• Correct answer
  C

  2, 3, 4
• D

  1, 2, 3, 4

Solution

Here statements 2, 3 and 4 are correct as follows
${\mathrm{H}}_2{\mathrm{O}}_2$ is weakly acidic, but more acidic than water.
${\mathrm{H}}_2{\mathrm{O}}_2+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_3{\mathrm{O}}^{+}+\mathrm{H}{\mathrm{O}}_2^{-}$
$2\mathrm{F}{\mathrm{e}}^{2+}+{\mathrm{H}}_2{\mathrm{O}}_2+2{\mathrm{H}}^{+}\to 2\mathrm{F}{\mathrm{e}}^{3+}+2{\mathrm{H}}_2\mathrm{O}$
${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4\rightleftharpoons {\mathrm{H}}^{+}+\mathrm{H}\mathrm{S}{\mathrm{O}}_4^{-}$

The peroxy disulphuric acid is hydrolysed separately to get ${\mathrm{H}}_2{\mathrm{O}}_2$ .
${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_5+{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$
${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_5+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4+{\mathrm{H}}_2{\mathrm{O}}_2$
$2\mathrm{M}\mathrm{n}{\mathrm{O}}_4^{-}+5{\mathrm{H}}_2{\mathrm{O}}_2+6{\mathrm{H}}^{+}\to 2\mathrm{M}{\mathrm{n}}^{2+}+8{\mathrm{H}}_2\mathrm{O}+5{\mathrm{O}}_2$

Hence, the correct answer is option: 'C'.