hey ppl help chem doubt

[fathimaash]

01. is an alkene oxidised by acidified potassium dicromate
02. will an alcohol undergo oxidation with both KMnO4 nd K2Cr2O7
02. can an aldehyde and ketone be reduced by H2 and nickel catalyst to primary nd seconary alcohol..
pls reply...
Thanx in advance

 

[leosco1995]

01. is an alkene oxidised by acidified potassium dicromate
02. will an alcohol undergo oxidation with both KMnO4 nd K2Cr2O7
02. can an aldehyde and ketone be reduced by H2 and nickel catalyst to primary nd seconary alcohol..
pls reply...
Thanx in advance

1. Nope. Alkenes can be oxidized by KMnO4 though.
2. Yes. But if you want an aldehyde, you have to use K2Cr2O7 and heat + distill off the product immediately. KMnO4 will directly give you an acid.
3. Yes, but if they ask you a reagent which reduces the C=O bond, you have to quote either NaBH4 in water or LiAlH4 in dry ether, not H2.

 

[fathimaash]

01.k y not by k2cr2o7?
02.how cn u get carboxylic acid directly using K2Cr2O7 conditions plss

 

[littlecloud11]

01.k y not by k2cr2o7?
02.how cn u get carboxylic acid directly using K2Cr2O7 conditions plss

1) k2cr2o7 isn't a strong oxidizing agent, and so it can't oxidize alkenes.
2) heat under reflux.