Information - simple lewis structures lewis structures are used to predict and accurately represent covalent bonging between atoms, keeping these limitations in mind: 1. the atoms h and he can only accommodate 2 valence electrons (duet rule). 2. the atoms the first row of the p-block (b to ne) can only accept 8 valence electrons (octet rule). 3. the atoms in lower rows of the p-block generally follow the octet rule but can accept more than 8 valence electrons, if that atom is central. based on your knowledge of atomic structure, what is the best reason why are h and he limited to accommodating only two electrons in a lewis structure? according the aufbau principle the 2s orbital of h and he can, at most, accept two electrons. according to the bernazzani rule there is insufficient volume in the h and he 1s valence orbital to accept more than 2 electrons. according to the soukhodolets principle h and he are not limited to two electrons in the 1s valence orbital and can possess any number of electrons. according the pauli principle the valence 1s orbital of h and he can, at most, accept two electrons.