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Can $\ce{H2SO4}$ oxidize $\ce{HCl}$ to $\ce{Cl2}$? I know that $\ce{KMnO4}$ can do it, but my question is considering $\ce{H2SO4}$. In sulfuric acid, sulphur is in +6 oxidation state and in $\ce{KMnO4}$, manganese is in +7 oxidation state. But sulphur is more electronegative than manganese, so I guessed that, $\ce{H2SO4}$ should be equally good oxidizing agent as $\ce{KMnO4}$.

However, I got to know that $\ce{KMnO4}$ can oxidising $\ce{HCl}$ to $\ce{Cl2}$ but $\ce{H2SO4}$ can't. Why it is so? I would also like to know which one has more oxidizing power and why?

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Concentrated sulfuric acid cannot oxidise chloride or fluoride, see here for a detailed explanation here

Concentrated sulfuric acid is not a strong enough oxidizing agent to oxidize fluoride or chloride. In those cases, only the steamy fumes of the hydrogen halide—hydrogen fluoride or hydrogen chloride—are produced. In terms of the halide ions, fluoride and chloride are not strong enough reducing agents to reduce the sulfuric acid. This is not the case for bromides and iodides.

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