Why in nitration of benzene we use concentrated sulfuric and nitric acid and not the dilute version of it? [closed]








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Is there any different if we use the dilute version? Most experiment I read in book use conc. acid but didn't explain why.




The first reaction happens in the mixture $\ce{HNO\_3 + H\_2SO\_4}$ : $$\ce{HNO\_3 + 2 H\_2SO\_4 -> NO\_2^+ + 2 HSO\_4^- + H\_3O^+}$$
Then benzene reacts with $\ce{NO\_2^+}$.
But water must be absent, because, if there is the smallest amount of water molecules, the ion $\ce{NO\_2^+}$ would immediately be destroyed. It would quickly react according to : $$\ce{NO\_2^+ + 2 H\_2O -> HNO\_3 + H\_3O^+ }$$ So this would prevent the reaction with benzene.


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