Sapling Question Number 20

[Ian_Lee_1E]

First of all, what are the differences between ionization energy, electron affinity, effective nuclear charge?

Second, the answer stated that " electron electron repulsion is responsible for oxygen having a lower first ionization energy than nitrogen. Recall that there are three orbitals in a 2p subshell. The 2p subshell of oxygen has a 2p4 configuration whereas the 2p subshell of nitrogen has a 2p3 configuration. In nitrogen, there is only one electron in each 2p orbitals. However in oxygen, one of the 2p orbitals is occupies by two electrons, and the resulting electrostatic repulsion gives oxygen's configuration a higher energy than nitrogen configuration. When one electron is removed from an oxygen atom, this paring energy is relieved and a more stable configuration is achieved. Therefore, the added energetic favorability of removing one electron from oxygen gives it a lower first ionization energy than nitrogen."

I dont understand this concept of stable configuration and oxygen electrostatic repulsion etc.

Could someone clarify?

[Katie Nye 2F]

Ionization Energy is the energy required to remove an electron from an atom. Electron affinity is the energy that is released when an electron is added to the shell of an atom. And effective nuclear charge, if I remember correctly, is the positive charge experienced by an electron that has more than one electron.

[305572629]

The periodic trend for ionization and electron affinity is the same: the closer to the top right of the periodic table, the stronger. For atomic radius: the closer to the bottom left, the larger the radius

[Hasmik Dis 2F]

For stable configuration, it's basically when valence electrons are full and thus the atom is stable. For electron repulsion: when comparing the radius of two atoms, the one with more electrons will have the largest radius because of electron-electron repulsion. Hope that answered your last question! :)

[Melanie Lin 3E]

Hi Ian!
This rule of having an electron in each orbital before filling them is actually the Hund's Rule! It basically states the order in which the orbitals are filled with electrons. Here's a link about Hund's Rule and how it works with orbital filling diagrams if you're curious: [https://courses.lumenlearning.com/cheminter/chapter/hunds-rule-and-orbital-filling-diagrams/]