Electron affinity

[Samantha Man 1L]

How does electron affinity change across the period table? Are there any trends?

[madisondesilva1c]

Electron affinity decreases down a group, and increases across a period. Therefore the trend is that higher up elements and further right elements have greater electron affinity. The trend is the same trend as ionization energy.

[Mayaal_Khan_4H]

Like electronegativity, electron affinity increases across a period and up a group because the electrons added to energy levels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons.

[Shash Khemka 1K]

Electron affinity increases through a period due to the fact that, as we go through a period, there is an increasing amount of valence electrons. The affinity would be the highest at the rightmost side of the periodic table because group 7 elements only need 1 more electron to complete their octet. Electron affinity increases up a group due to the energy level of the electrons.

[Amy Dinh 1A]

An exception to the trend is that the electron affinities of the elements in column 15 are lower than those of column 14.

For example, if we needed to rank C, N, O, F in order of increasing electron affinities, the order would be N<C<O<F.

[AdityaGuru1H]

the exception also applies to phosphorus so for the 3rd row it would be P<Si<S<Cl