Ionization Energy Trend

[Danielle Goldwirth 3F]

Why does ionization energy increase from down to up on the periodic table?

[Brandon Pham 1B]

Moving down a group, an energy level is added. The outermost electrons are further from the nucleus, thus easier to remove.

[Elena Chen 2B]

Ionization energy is defined as energy need to remove an electron from an atom. The further away an electron is from the nucleus, the easier it is to remove because of the lessened nuclear attraction. As you move up the periodic table, the shell number n decreases, meaning the electrons are closer to the nucleus at the top of the periodic table compared to the bottom. So, there is more nuclear pull on each electron, resulting in more energy need to pull the electron away from the atom.

Hope this helps!

[Joseph Hsing 2C]

I believe ionization energy increases as you move up a group because the valence electrons are getting closer and closer to the nucleus, thus needing more energy to counteract the attraction of electrons with the nucleus. Basically, less shielding effect.

[Alejandro Gonzalez 2G]

I think ionization energy increases as you move towards the top of the periodic table because of how close the electrons are to the nucleus, whereas elements with many shells have less pull on the outermost electrons.

[David Jen 1J]

This is because the lower the molecule on a table, the bigger it is, thus it is easier to remove an electron from it's outer shell compared to a smaller molecule because the level of attraction is lower.

[Nick Saeedi 1I]

The elements down a group have electrons farther away from the nucleus so it is easier to remove and takes less ionization energy.