Smallest unit that consists of at least two atoms is neutrons protons molecules electrons

Answer;

Molecules

Explanation;Atoms are the smallest component of an element having the chemical properties of the element.Molecules is a group of two or more atoms bonded together. Molecules may be of the same atoms or of different atoms.That is; in a molecule of an element, all the atoms are the same, while in a molecule of a compound atoms are different.  For example, in a molecule of water (a compound), there is one oxygen atom and two hydrogen atoms. But in a molecule of oxygen (an element), both of the atoms are oxygen.