[gracie]

 Just a quick question on why sulphuric acid is used as the solvent when making up potassium dichromate and potassium permanganate?
 In the case of the KMnO4 i know that HCl is unsuitable as the Cl is an oxidising agent but other than the stability of potassium dichromate in H2SO4, im not sure.
            Thanks.

[Garneck]

Cl- is a reducing (not oxidising) agent for KMnO4. (Or my chemistry english is getting bad)

I'd say it's because of the same reason. K2Cr2O7 is a strong oxidiser.

Oh, and when they reduce, H+ causes them to reduce to lower oxididation states. In H+, permangate MnO₄^- reduces to Mn²⁺, while in OH- only to MnO₄^2-