an atom is the smallest unit of matter or a substance.
Explanation:
the structure of the
atom consists of electrons, protons, neutrons) which makes up the nucleus is more than a hundred thousand times smaller than it's atom but makes up 99.9% of the mass of the atom.
the protons are the positively charged particles. The neutrons are the negatively charged particles. The electrons are the negatively charged particles.
the first energy level consists of two electrons. the second energy level consists of eight electrons. the 3 energy level consists of eighteen electrons. the 4 energy level consists of thirty two electrons.
