Electron Withdrawal and Acidity: Exploring the Relationship between C and H

[leopard]

Why is a) more acidic than b) when C is more electron withdrawing than H? Electron withdrawal by a substituent increases acidity...

 

[GCT]

Why is a) more acidic than b) when C is more electron withdrawing than H? Electron withdrawal by a substituent increases acidity...

Consider the fact that the CH3 group is electron donating relative to H and what influence this would have on the conjugate bases.

 

[Blueshift5]

I can explain the relationship between electron withdrawal and acidity in the context of organic chemistry. In organic molecules, acidity is determined by the stability of the conjugate base formed after deprotonation. A more stable conjugate base leads to a stronger acid.

In the case of a) and b), we are comparing two different molecules with the same functional group (e.g. carboxylic acid) but with different substituents attached to the carbon atom. The substituent in a) is more electron withdrawing than the substituent in b). This means that the substituent in a) has a greater ability to pull electrons towards itself, making the carbon atom more electron deficient.

In a) where the substituent is more electron withdrawing, the carbon atom is more electron deficient and therefore less able to stabilize the negative charge on the conjugate base. This results in a less stable conjugate base and a stronger acid.

On the other hand, in b) where the substituent is less electron withdrawing, the carbon atom is less electron deficient and therefore better able to stabilize the negative charge on the conjugate base. This results in a more stable conjugate base and a weaker acid.

In summary, the relationship between electron withdrawal and acidity is that a more electron withdrawing substituent leads to a less stable conjugate base and a stronger acid, while a less electron withdrawing substituent leads to a more stable conjugate base and a weaker acid. This is why a) is more acidic than b) when the substituent on carbon is more electron withdrawing than the substituent on hydrogen.