Acidified potassium dichromate

[ATB_roo]

When acidified potassium dichromate is used in organic chemistry to oxidise alcohols, nearly all the text books state the colour change is 'from organge to green'. But when I do the experiments in the lab the colour change is normally orange to blue. Why is this?

Does that fact that the alcochol is oxidised to a carboxylic acid (green) but then the oxidation continues till the carboxylic acid oxidised to carbon dioxide and water, which possibly creates a blue colour? I don't really know, thats just a guess.

Thanks

[growlybear]

Are you using Schiff's reagent. Sometimes its composition can change.

[ATB_roo]

I've never heard of Schiff's reagent so I don't think we have been using it. Thank you anyway though.

[heathfield]

Could there be a possible explanation here?