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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: iyc on December 26, 2004, 04:58:10 AM

Title: Acidified with...
Post by: iyc on December 26, 2004, 04:58:10 AM
Why should we acidified some oxidzing agent like KMnO4, KCr2O7 with dilute H2SO4?  ???Why not using dilute HNO3 or diluteHCl to acidified?
Title: Re:Acidified with...
Post by: Donaldson Tan on December 26, 2004, 09:04:32 PM
the half reactions for oxidisng process by these reagents are favoured by acidic environment.

You cant use HNO3 or HCl becuase their conjugate based will be oxidised to form hazardous products. Oxidising chloride ions yield chlorine gas and oxiding nitrite ions produce NO2. Both gas are hazardous..
Title: Re:Acidified with...
Post by: AWK on December 27, 2004, 06:13:58 AM
HCl reacts with KMnO4 and K2Cr2O7 to produce chlorine.
Sometimes nitric acid is used instead of H2SO4, eg when you oxidise something using PbO2 or sodium bismuthate (NaBiO3) to prevent precipitation