Answer:
They are made up of elements.
Explanation:
An atom is the smallest particle of matter that still retains the property of the element.
Two or more atoms combine to form elements or compounds. Elements are formed by two or more similar atoms, while compounds are formed by two or more different elements.
Atoms are made up of subatomic particles, protons, electrons and neutrons. Electrons are negatively charged, protons are positively charged while neutrons have no charge.
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