Periodic Table & Electron Affinity

[noelle_lipschutz_3F]

Can someone explain how to use the periodic table to determine electron affinity?

[Aaina 2D]

Hi! Electron affinity is basically the opposite of ionization energy. It's the energy released when electrons are added to a gas phase atom. It's not as periodic, but there's usually high e- affinity for elements in the top right of the periodic table. Halogens (group 17) have high e- affinities.

In general, the trend in the periodic table for e- affinity is: increases across a period and decreases down a group. Hope this helps!

[Shalyn Kelly 3H]

Hi! All of what's above, and I also think it's a generally good idea to have a mini periodic table somewhere in your notes/review materials with all of the trends (atomic radius, ionization energy, electron affinity) written down (color-coded if you want) to help memorize what they are. Like ionization energy and electron affinity decrease down a group and increase across a period, while atomic radii (and ionic I think) increase down a group and decrease across a period.
If you want to look up "periodic table trends" I believe most of them show the trends with arrows going from smaller to larger.

[Lisa Wang 3B]

electron affinity is the energy that gets released when an electron has been added to the atom, undergoing an exothermic process. Like the above posts had said, the affinity increases across the period and decreases down the group, similarly to the ionization energy.

[David Y]

increases across a period and decreased down a group

[Dominic Benna 2E]

Can someone explain how to use the periodic table to determine electron affinity?

I believe that affinity increases as you go right down a period it increases and decreases as you go down a row!

[Jayasree Peri 2J]

The main goal of elements regarding electrons is that they want to achieve a full valence shell (all the electrons they can have in their last energy level) to be stable. If the element is towards the right side of the periodic table, that means it has more electrons in its valence shell, so it's easier to just complete that shell by adding a few electrons. If the element is towards the left side of the periodic table, it is easier to just remove a few electrons from the valence shell; this will get rid of that shell and make the second-to-last energy level the new valence shell.

[SelenaDahabreh1D]

Simply put, electron affinity increases as you move up a group and across a period. So, for example, Oxygen would have a higher electron affinity than Nitrogen and Sulfur.

[805593945]

Just because the the noble gases are after the halogen do not mean that they have higher electron affinity than the halogen. In fact, they don't want anymore electrons because they have already fulfilled the octet rule.

[Mingzi Yang 1E]

Generally elements with high electron affinity are in top right of periodic table (group 17). Electron affinity increases across a period and decreases down a group.

[Heidi Buri 2I]

Electron affinity depends on the number of valence electrons that an atom has. When there are more valence electrons, the more likely the atom will gain electrons. The number of valance electrons ca be observed on the periodic table. I believe that on a periodic table, the electron affinity decreases from the top down of groups and from the right to left on the rows. This is the same for all groups and rows on the periodic table.

[Nhu Pham-Dis3G]

Hi! There are many ways that you can look at the periodic table to determine electron affinity. Some of the general patterns to note is that electron affinity increases across the period and also increases up a group.