Finding ground state e- configuration

[JacksonWissing2G]

Can somebody explain how we can apply the pauli exclusion principle and hund's rule to find the ground state e- configuration? I'm a little confused about it.

[Anne Mariano 3F]

Pauli Exclusion Principle is the reason for spin quantum numbers as it makes sure that two electrons cannot be identified by the same quantum numbers. Thus, the electrons have different spins. Those electrons in the same orbital would all be unique in numbers. Hund's Rule is when one electron goes into each orbital available until all are half full. Then, the remaining electrons are paired up in each orbital. Electron configuration is then found using these ideas to draw out the diagrams. When filling up the orbitals, you know that the electrons need to spin differently in each one. Then with Hund's Rule, the correct distributions of electrons.

[Samantha Melin 2E]

When discerning electron configurations, you have to take both the Pauli Exclusion Principle and Hund's Rule into account. The Pauli Exclusion Principle states that no more than two electrons can be in in the same orbital. When two electrons are in the same orbital, they are spin paired, thus making it so that no two electrons can be identified by the same quantum numbers. Hund's rule means that when electrons are filling in an orbital that is not at full occupancy, they will be parallel to one another (they will have the same spin). As the subshell fills, electrons will be paired with a second electron with an opposite spin. Hund's rule occurs because of electron repulsion.

[Neeti Indiresan 3I]

The Pauli Exclusion Principle tells us that each orbital can only contain 2 electrons. For instance, in a p subshell with 3 orbitals, each can only carry 2 electrons, each with an opposite spin. Hund's rule tells us that when electrons are filling in, due to same charge repulsion, they will fill in empty orbitals first with parallel spins. For example, if we have an atom that has 3 electrons in the p subshell, we would expect to see 1 electron in each orbital, each with the same spin, rather than one orbital with 2 electrons and 1 orbital with the remaining electron. If we had 4, 5, or 6 electrons in our p orbital, we would see those electron pairs fill in after each orbital has one electron.

[Riya Sawhney 1C]

What everyone said is helpful, but I also think examples can help a lot. For example, Nitrogen. Nitrogen in the ground state has 7 electrons because it has 7 protons in the nucleus (so we would say Z=7 where Z is the number of electrons). The electron configuration in ground state, using the principles stated in other responses, is 1s^22s^2Px^2Py^12Px^1. As you can see the Px, Py and Pz orbitals each have one electron in them, and the reason for this is stated in Hund's Rule. However, you can assume this and how you would actually write this electron configuration would be 1s^22s^22P^3.