Carbohydrates are biomolecules made up of carbon (C), hydrogen (H), and oxygen (O) atoms, usually in a 2:1 hydrogen-to-oxygen ratio, like water. The general empirical formula is Cm(H2O)n, where m and n might vary depending on the carbohydrate.
Carbon is the structural framework of carbohydrates. It is the essential component that creates rings or chains in carbohydrates. Carbon can create complex carbohydrates (like starch and cellulose) and simple sugars (like glucose). Hydrogen atoms are bonded to carbon atoms, which balances the molecule’s structure. They also help to create water molecules during glucose breakdown. Hydrogen provides carbohydrates with their energy-storing capacity because the bonds between carbon and hydrogen are high in energy. The carbohydrate structure contains oxygen atoms, which are important in the creation of hydroxyl groups (-OH) and carbonyl groups (C=O). These groups contribute to carbohydrate’s chemical reactivity and solubility in water.
For Example:
Molecules such as formaldehyde (CH2O) and acetic acid (C2H4O2) have the carbohydrate formula but are not categorized as carbohydrates because they lack the typical hydroxyl and carbonyl arrangement of sugars.