Question

What systematic ending is used to show that a molecule is a carboxylic acid? Give an example.

Short answer

The systematic ending used to show that a molecule is a carboxylic acid is "-oic acid." A common example of a carboxylic acid is ethanoic acid (CH3COOH), also known as acetic acid.

Step-by-step solution

1. Identify the systematic ending of carboxylic acids.

Carboxylic acids are organic compounds containing a carboxyl functional group (COOH). The systematic (IUPAC) naming for carboxylic acids ends with the suffix "-oic acid."

2. Provide an example of a carboxylic acid.

A common example of a carboxylic acid is ethanoic acid (also known as acetic acid). Its IUPAC name, ethanoic acid, follows the systematic naming convention we mentioned earlier. The structural formula for ethanoic acid is CH3COOH or more explicitly: H H | | H-C-C=O | -OH

Key concepts

Organic Chemistry

Organic chemistry is a branch of chemistry that studies carbon-based compounds and their reactions. The vast array of organic compounds is due to carbon's unique ability to form stable bonds with itself and other elements, producing complex structures varying from simple hydrocarbons to large biomolecules. Masters of the organic realm can predict how these molecules will behave and react, making this field a cornerstone of medicine, pharmacology, and materials science.

Understanding functional groups such as the carboxyl group is key to deciphering the properties and reactivity of organic molecules. For instance, the carboxyl group found in carboxylic acids makes these compounds acidic and enables them to participate in a variety of important reactions, such as esterification. Recognizing various functional groups helps us rationalize why a molecule like ethanoic acid acts as a vinegar essence and also why it plays an integral role in metabolic processes.

IUPAC Nomenclature

IUPAC nomenclature is a systematic method of naming chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC). It provides a standardized set of rules that chemists around the world can use to name a vast number of compounds unambiguously.

When applying IUPAC rules to carboxylic acids, one must identify the longest carbon chain including the COOH group and apply the suffix '-oic acid' to the corresponding alkane's name. This systematic approach removes the confusion that might arise from the various common names substances may have.

Identifying the Root Structure

The root word in the IUPAC name indicates the number of carbon atoms in the longest continuous chain. For example, 'ethanoic acid' implies a two-carbon chain carboxylic acid.

Adding the Functional Group

Finally, by placing the 'oic acid' ending, the presence of the carboxyl functional group is confirmed in the compound, clearly identifying it as a carboxylic acid.

Functional Groups

Functional groups in organic chemistry are specific groupings of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. These groups can be thought of as the reactive parts of a molecule that determine its function.

The carboxyl group (-COOH) is an example of a functional group relevant to carboxylic acids. It consists of a carbonyl group (a carbon double bonded to an oxygen) and a hydroxyl group (an oxygen bonded to a hydrogen). This arrangement allows carboxylic acids to release a hydrogen ion (H+) in solution, which is why they are acidic. It is the carboxyl group that gives all carboxylic acids their common properties, and it is this similarity that provides cohesiveness to organic chemistry as a subject.

Reactivity and Properties

This particular functional group makes these compounds versatile in chemical reactions. Recognizing this functional group is essential when predicting the behavior of organic molecules in different environments, such as in biochemical pathways or industrial processes.