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Q.
$Cr_{2}O^{2-}_{7}+X \xrightarrow{ H^{+} }Cr^{3+}+H_{2}O$ + oxidised product of $X$ . $X$ in the above reaction cannot be
Redox Reactions
Solution:
$Cr_{2}O^{2-}_{7}+ X \xrightarrow{ H^{+} }Cr^{3+}+H_{2}O$ + oxidised product of $X$ In the given reaction $X$ is oxidised and hence acting as reducing agent. Out of given choices $SO^{2-}_{4}$ cannot act as reducing agent, because sulphur is present in its highest oxidation state, $+6$