Aldehyde
Definition and meaning of Aldehyde in chemistry.
An aldehyde is an organic compound containing a carbonyl group (C=O) bonded to at least one hydrogen atom, with the general structure R-CHO. Aldehydes are readily oxidized to carboxylic acids and serve as important intermediates in organic synthesis and industrial manufacturing.
In more detail
The aldehyde functional group consists of a carbon atom double-bonded to oxygen and single-bonded to a hydrogen atom, typically positioned at the end of a carbon chain. This terminal placement makes aldehydes significantly more reactive than their isomeric ketones, because both the hydrogen atom and the carbonyl carbon are vulnerable to oxidation and nucleophilic attack respectively. Aldehydes occur naturally throughout the environment in essential oils, plant extracts, and as intermediates in metabolic pathways within living cells. They are extensively used in industry for synthesizing polymers, resins, pharmaceuticals, dyes, and countless other organic compounds central to modern chemistry.
Key facts
| Field | Organic Chemistry |
|---|---|
| Chemical formula | R-CHO (general structure); acetaldehyde CH3CHO; formaldehyde HCHO |
| Functional group | Carbonyl (C=O) bonded to at least one hydrogen atom |
| Reactivity | Easily oxidized to carboxylic acids; susceptible to nucleophilic attack |
Acetaldehyde (CH3CHO) is produced naturally during alcohol fermentation and is a key precursor in the synthesis of acetic acid, acetic anhydride, and various polymers used in consumer products.
Frequently asked questions
How do aldehydes differ from ketones?
Aldehydes have the carbonyl group at a terminal position bonded to one hydrogen atom, while ketones have it in an internal position bonded to two carbon atoms.
What is formaldehyde?
Formaldehyde (HCHO) is the simplest aldehyde, widely used as a disinfectant, preservative, and starting material for manufacturing resins and polymers.