What mostlt determines the chemical properties of the atoms of an element

The chemical properties of an element are determined by the configuration of its electrons in orbit around its nucleus.

Explanation:

The number of electrons in each element’s outermost valence shell, is the primary factor in determining its chemical properties. The number of electrons in an atom are equal to the number of protons in the nucleus so the electrical charges balance each other. The number of protons in the nucleus of an atom is its Atomic Number.

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