In a typical reaction, the preferred form of ketones and aldehydes is:

In a typical reaction involving ketones and aldehydes, the preferred form is the keto form. This is primarily due to the stability of the keto form compared to its alternative structures, such as enols or hydrates.

The keto form, characterized by a carbonyl group (C=O), is usually more stable because the carbonyl bond is relatively strong and the molecule can adopt a more favorable electronic configuration. Ketones and aldehydes are generally in equilibrium with their enol forms, which contain a hydroxyl group (–OH) attached to an adjacent carbon with a double bond, but this enol form is generally less favored.

Enols are more reactive and less stable than their corresponding keto forms due to factors such as steric hindrance and the less favorable conformation of the double bond when compared to the carbonyl group. In most reactions and under standard conditions, the keto form predominates because it allows for stronger dipole interactions between the carbonyl oxygen and nearby functional groups, contributing to overall stability.

While hydrates (the addition of water molecules) and acidic forms do exist in specific contexts, they are not the most stable or predominant forms in the majority of reactions involving ketones and aldehydes. Thus, the keto