a. What do we know about any quantum-physical law, dictating 8 electrons in the outer atomic shell + the other shells' populations, including the 2 electrons in the innermost. Any physical theory behind these numbers, or just an empirical reality ? b. How reacting atoms 'choose' between, e.g., ionic bond and covalent bond ? c. What Hydrogen was used in the early spectra measurements (e.g., Balmer) - atomic or molecular ? Since the spectra are atomic in nature, how did they split the H molecule into two atoms in those days ?