[davidclever]

what are the products form when potassium dichromate reacts with sulphuric acid???

[Alpha-Omega]

Potassium dichromate / sulfuric acid:   (chromosulfuric acid) 

Eqn: K₂Cr₂O₇ + 4H₂SO₄   ------> 2KCr(SO₄)₂   + 7H₂O

This material has many uses.  It can be used as a cleaning agent for laboratory glassware.  Potassium dichromate (usually acidified with sulfuric acid), or any other dichromate for that matter, can be used to determine the amount of ethanol in a solution using back titration.   It can also be used as a universal visualization reagent for organic compounds (e.g,, alcohols, bile acids, lipds) in TLC (thin layer chromatography) analyses.