alpha carbon confusion

[Dental2000]

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Very basic question , but i keep getting confused...

CH3CH2OH
CH3COCH3
CH3CHO

I know for the alchole the alpha carbon is the carbon directly attached to -OH

but im having a little trouble with aldehydes and ketons...

for the ketone is the alpha carbon directly attached to the =O or the carbon attached to -C=O ?

for aldehydes which will the alpha hydrogen be ?

 

[crax]

attached to oxygen is carbonyl, then alpha, beta, gamma. 2-propanone (acetone) has two alpha carbons, one to the left of the carbonyl and one to the right.

 

[toothhornet88]

Very basic question , but i keep getting confused...

CH3CH2OH
CH3COCH3
CH3CHO

I know for the alchole the alpha carbon is the carbon directly attached to -OH

but im having a little trouble with aldehydes and ketons...

for the ketone is the alpha carbon directly attached to the =O or the carbon attached to -C=O ?

for aldehydes which will the alpha hydrogen be ?

alpha carbons are the first carbons that are attached to the functional group

So for ketones alpha carbons would be either CH3's on both sides (it is the carbon attached to -C=O because C=O is the functional group; same goes for aldehydes)
For aldehydes the alpha carbon would be the CH3
For ethyl alcohol it would be the carbon attached to the alcohol

...hope it helps!