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How does hydrolysis use water to break apart a compound?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

Hydrolysis is a chemical process involving the scission, or cleavage, of a molecule through its reaction with water. In this double decomposition reaction, water acts as a reactant, effectively breaking a compound apart by inserting its own constituent elements into the resulting products.12

If a compound is represented by the formula $A B$ and water by $H O H$ , the general hydrolysis reaction can be expressed as:
$A B + H O H ⇌ A H + B O H$

During this process, the water molecule is split, with its components becoming attached to the fragments of the original compound. For example, in the hydrolysis of an ester, a covalent bond forms between the oxygen atom of the water molecule and the carbon atom of the ester. Subsequently, the carbon-oxygen bond of the ester breaks, and hydrogen ions from the water molecule attach to the nascent alcohol molecule, while the remaining hydroxyl group attaches to the acid component.2

These reactions are essential in biological systems, where enzymes catalyze the breakdown of complex molecules like proteins, fats, and starches into simpler, assimilable forms.32