Which of the following are a. hemiacetals? b. acetals? c. hydrates?
4.

Verified step by step guidance

1. Step 1: Understand the definitions of the terms provided in the question. A hemiacetal contains one hydroxyl group (-OH) and one alkoxy group (-OR) attached to the same carbon atom. An acetal contains two alkoxy groups (-OR) attached to the same carbon atom. A hydrate contains two hydroxyl groups (-OH) attached to the same carbon atom.
2. Step 2: Analyze the given chemical structure (CH3)2C(OH)2. This molecule has two hydroxyl groups (-OH) attached to the same carbon atom, which matches the definition of a hydrate.
3. Step 3: Compare the structure to the definitions of hemiacetals and acetals. Since the molecule does not contain any alkoxy groups (-OR), it cannot be classified as a hemiacetal or an acetal.
4. Step 4: Confirm the classification of the molecule as a hydrate based on the presence of two hydroxyl groups (-OH) attached to the same carbon atom.
5. Step 5: Conclude that the molecule (CH3)2C(OH)2 is a hydrate and does not fall under the categories of hemiacetals or acetals.

Key Concepts

Hemiacetals

Hemiacetals are formed when an aldehyde or ketone reacts with an alcohol, resulting in a compound that contains both an alcohol (-OH) and an ether (-O-) functional group. They typically exist in equilibrium with their corresponding carbonyl compounds and are characterized by having one -OH group and one -OR group attached to the same carbon atom.

Acetals

Acetals are derived from hemiacetals through a reaction with an additional alcohol, leading to a compound with two -OR groups attached to the same carbon atom. This transformation involves the loss of water and is significant in organic synthesis, as acetals are often more stable than their hemiacetal precursors and can serve as protecting groups for carbonyl functionalities.

Hydrates

Hydrates are formed when water adds to a carbonyl compound, such as an aldehyde or ketone, resulting in a molecule that contains two -OH groups attached to the same carbon atom. This process is reversible and is important in various biochemical pathways, as it can influence the reactivity and stability of carbonyl compounds in aqueous environments.