Question

Draw the smallest molecule that can have a separate aldehyde and carboxylic acid group.

Short answer

The smallest molecule is 3-oxopropionic acid with separate aldehyde and carboxylic groups.

Step-by-step solution

Understanding Aldehyde and Carboxylic Acid Groups

An aldehyde group is characterized by the functional group (-CHO), while a carboxylic acid has the functional group (-COOH). Both groups must be present in the molecule on separate carbon atoms.

Choosing the Simplest Carbon Skeleton

To satisfy the condition of having separate aldehyde and carboxylic acid groups, we choose the smallest possible carbon skeleton that can accommodate both. This is a three-carbon chain, known as propanal.

Placing the Functional Groups

Place the carboxylic acid group (-COOH) at one end of the propane chain (carbon 1) and the aldehyde group (-CHO) at another carbon (carbon 3), ensuring they are on separate carbons.

Final Molecule Structure

The molecule is called 3-oxopropionic acid. It has one aldehyde group on the 3rd carbon atom and one carboxylic acid group on the 1st carbon atom.

Key concepts

Molecular Structure

Molecular structure refers to the arrangement of atoms and the chemical bonds that hold these atoms together within a molecule. For any organic compound, understanding its molecular structure is crucial, as it determines the molecule's properties and reactivity.

In this particular exercise, the molecular structure involves arranging a carbon backbone in such a way that it accommodates both an aldehyde group and a carboxylic acid group. When we talk about the smallest possible molecule having both these groups with separate carbon atoms, the attention is on the carbon chain length. Here, a three-carbon chain provides just the right structure to host these functional groups sufficiently.

The molecule, known as 3-oxopropionic acid, demonstrates how functional groups are spatially arranged within a structured carbon backbone. This logical arrangement of atoms contributes to the molecule's ability to perform specific chemical reactions and interactions.

Functional Groups

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. In organic chemistry, recognizing functional groups provides insights into the behavior and reactivity of a compound.

Two key functional groups in this exercise are the aldehyde group and the carboxylic acid group.

• The aldehyde group is characterized by the presence of a carbon atom double-bonded to an oxygen atom (carbonyl group) and single-bonded to a hydrogen atom, denoted as (-CHO).
• The carboxylic acid group features a carbon atom that is bonded to a hydroxyl group (-OH) and a double-bonded oxygen atom (carbonyl), typically represented as (-COOH).

Understanding how these groups influence the overall chemistry of a molecule is essential. They each provide unique sites for chemical reactions, allowing the molecule to interact and transform in numerous ways, dependent on conditions and reagents.

Aldehyde

An aldehyde is a type of organic compound that features a carbon atom bonded to a hydrogen atom and double-bonded to an oxygen atom, forming the functional group (-CHO). This group is typically found at the end of a carbon chain, which influences how the molecule reacts chemically.

Aldehydes are known for their role in synthesis reactions, where they can participate in several types of chemical transformations due to the polar nature of the carbonyl group (C=O) present in them.

Identifying the position of the aldehyde group within a molecule is crucial for determining the naming of the compound and predicting its behavior in reactions. In our exercise, the aldehyde group is located at the third carbon atom of a three-carbon chain, forming part of the molecule named 3-oxopropionic acid.

Carboxylic Acid

Carboxylic acids are organic compounds highlighted by the presence of a carboxyl group (-COOH), which consists of a carbonyl (-C=O) and a hydroxyl (-OH) group attached to the same carbon atom. These acids are noted for their acidic nature due to the ability of the carboxyl group to release a proton (H+) in aqueous solutions.

This group significantly impacts the acidity and solubility of the molecules in which it is present, and it's a common feature in a vast array of organic substances, including amino acids and fatty acids.

In the context of 3-oxopropionic acid, the carboxylic acid group is positioned at the first carbon atom of the carbon chain. This placement affects both the molecule's structure and its reactivity, making it a versatile participant in esterification reactions among others. Understanding its position and function is vital for grasping the molecule's chemical characteristics and reactivity.