Which of the following reactions do not involve oxidation reduction?I. 2Cs+2H2O⟶2CsOH+H2II. 2CuI2⟶2CuI+I2III. NH4Br+KOH⟶KBr+NH3+H2OIV. 4KCN+Fe(CN)2⟶K4Fe(CN)6

I. Cs→Cs1++e−(Oxidation) H2O+e−⟶O⊙H+12H2 (Reduction)Hence, redox reaction II. e-+Cu2+→ Cu1+(Reduction)2I⊝→ I2+2e-(Oxidation)                                                            Hence, redox reaction.III. ⊕NH4x=-3→ NH3x=-3(No change in oxidation number ) Hence, reaction is not redox IV. No change in the oxidation number of either Fe2+ or CN⊝ in both reactant and product; hence, not redox reaction