Wednesday, September 19, 2007.

Ok I AM STUMPED.

my freaking lousy bio textbook screams that reducing sugars are reducing sugars only because there is the presence of an aldehyde or/and ketone group. our bio teacher has been teaching us that.

I have no probs with the aldehyde part-it makes common sense.
Primary alcohol-(oxidation)-aldehydes-(oxidation)-carboxylic acids

BUT EVERYONE KNOWS, A KETONE GROUP CANNOT BE FREAKING OXIDISED UNLESS BY VERY STRONG OXIDISING AGENTS! (F2 not so sure, conc. H2Cr2O7/H2CrO4 surely, hot HNO3 ya, but anything else????)

Secondary alcohol -(oxidation)-ketones

SO WHO SHOULD I TRUST? my bio textbook, which says on page 34 (i think) that NH3 can't form hydrogen bonds OR general chem which evidently says ketones can be reduced easily to secondary alcohols but evidently says that that it is quite impossible to oxidise ketones.

Look ar-

Primary alcohol- RCH2OH + O - RCHO (aldehyde) + O - RCOOH
Secondary alcohol - R1CHOHR2 + O - R1COR2 (ketone) then STOP! No more dehydrogenation can occur since no more hydrogen left to dehydrogenate! thus oxidation (loss of hydrogen) cannot occur!
Tertiary alcohol another thing lar, R1COHR2R3 is resistant to oxidation.

SO WHAT NOW FOR EOYS? TRUST THE LOUSY BOOK AND PASS OR TRUST MYSELF AND FAIL? arrgh.

p.s. 10 more days. can't wait any longer.

Labels: chem