Final answer:
The most basic unit of a compound is an atom.
Step-by-step explanation:
An atom can represent the most basic unit of a compound. Compounds are made up of different elements, which are composed of atoms. Atoms are the smallest indivisible particles of an element that retain its chemical properties. For example, in water (H2O), the basic unit is an atom of oxygen (O) bonded to two atoms of hydrogen (H).
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