Category: Aufbau Principle

The element nitrogen has 7 electrons (since its atomic number is 7). The electrons are filled into the 1s, 2s, and 2p orbitals. The electron configuration of nitrogen can be written as 1s22s22p3

Writing the Electron Configuration of Sulphur The atomic number of sulphur is 16, implying that it holds a total of 16 electrons. As per the Aufbau principle, two of these electrons are present in the 1s subshell, eight of them are present in the 2s and 2p subshell, and the remaining are distributed into the… Continue reading Electronic Configuration using the Aufbau Principle

The electron configuration of chromium is [Ar]3d54s1 and not [Ar]3d44s2 (as suggested by the Aufbau principle). This exception is attributed to several factors such as the increased stability provided by half-filled subshells and the relatively low energy gap between the 3d and the 4s subshells. The energy gap between the different subshells is illustrated below. Half filled subshells feature… Continue reading Exceptions

According to the Aufbau principle, electrons first occupy those orbitals whose energy is the lowest. This implies that the electrons enter the orbitals having higher energies only when orbitals with lower energies have been completely filled. The order in which the energy of orbitals increases can be determined with the help of the (n+l) rule,… Continue reading Salient Features of the Aufbau Principle

What is the Aufbau Principle? The Aufbau principle dictates the manner in which electrons are filled in the atomic orbitals of an atom in its ground state. It states that electrons are filled into atomic orbitals in the increasing order of orbital energy level. According to the Aufbau principle, the available atomic orbitals with the… Continue reading Aufbau Principle