Which of the following is/are redox reaction(s)? — Redox Reactions and Volumetric Analysis Chemistry Question

💡 Solution & Explanation

**(A)** In $BaO_2$, Oxygen is in peroxide state (-1). In $H_2O_2$, it remains -1. $Ba, S, H$ states are unchanged. <br>**(B)** $Cl$ changes from +5 to -1 and $O$ from -2 to 0. <br>**(C)** $Fe$ in the complex changes from +2 to +3, while $Cl$ changes from 0 to -1. <br>**(D)** $S$ in $SO_2$ is +4 and in $H_2S$ is -2. Both go to 0 in elemental sulfur (comproportionation). [1, 2]