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CBSE Class 12-science Answered

methods of preparations of aldehydes n ketones???

Asked by seema behera | 26 Jul, 2012, 04:11: PM

Expert Answer

Oxidising alcohols to make aldehydes and ketones

The oxidising agent used in these reactions is normally a solution of sodium or potassium dichromate(VI) acidified with dilute sulphuric acid. If oxidation occurs, the orange solution containing the dichromate(VI) ions is reduced to a green solution containing chromium(III) ions.

The net effect is that an oxygen atom from the oxidising agent removes a hydrogen from the -OH group of the alcohol and one from the carbon to which it is attached.

R and R' are alkyl groups or hydrogen. If at least one of these groups is a hydrogen atom, then you will get an aldehyde. If they are both alkyl groups then you get a ketone.

Answered by | 26 Jul, 2012, 07:22: PM

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CBSE 12-science - Chemistry

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