Molecules. Atoms glued by bonds; nuclei incarcerated by electrons; electrons forming an inhomogeneous gas contained not by outer walls but by an electrostatic potential in its interior ironically named ‘external potential’. Molecules. The study object of chemists. The fundamental construct on which the chemical understanding of the universe relies.
Ten electrons, ten protons, and ten neutrons, giving rise to various electronic densities, various chemical properties: CH4, NH3, H2O, HF; which is it?
Atoms are letters, molecules are words; Chemistry, their unabashed poetry.