Why does electron affinity decrease going down?

When moving down a group, the electron affinity generally decreases. This is because as you go down the period table, new valence shells are added increasing the atomic radius. The new orbital is further away from the nucleus, meaning the attraction between the positively charged nucleus and the new electron decrease.

Does electron affinity decrease across a period?

Electron affinity generally increases across a period in the periodic table and sometimes decreases down a group. The chemical rationale for changes in electron affinity across the periodic table is the increased effective nuclear charge across a period and up a group.

What factors determine electron affinity?

Various factors that affect electron affinity are atomic size, nuclear charge and the symmetry of the electronic configuration. Atomic size: With increase in the atomic size, the distance between the nucleus and the incoming electron also increases.

Why does electron affinity decrease from top to bottom and increase left to right?

Electron affinity increases from left to right within a period. This is caused by the decrease in atomic radius. Electron affinity decreases from top to bottom within a group. This is caused by the increase in atomic radius.

Why does electron affinity tend to become more exothermic as you move right across a period?

Electron affinity (the energy associated with forming an anion) is more favorable (exothermic) when electrons are placed into lower energy orbitals, closer to the nucleus. Therefore, electron affinity becomes increasingly negative as we move left to right across the periodic table and decreases as we move down a group.

Why is there a decrease in electron affinity going from lithium to sodium?

So they have less electron affinity. This is why sodium has less electron affinity than lithium because it is a larger atom, it has a it has more electrons. So whenever it is given an extra electron it does not have as much affinity for that electron.

How does electron configuration relate to electron affinity?

Electron affinity decreases or increases across a period depending on electronic configuration. This occurs because of the same subshell rule that governs ionization energies. Since a half-filled “p” subshell is more stable, carbon has a greater affinity for an electron than nitrogen.

How does electron configuration affect electron affinity?

Why does electron affinity increase from bottom to top?

Lesson Summary The general trends of the electron affinity are that it increases from left to right across the periodic table due to an increase in the nuclear charge, and it increases from bottom to top due to the effect of atomic size.

How does electron affinity change when we move from left to right in a periodic table?

In general, electron affinities become more negative as we move from left to right on the periodic table. In general, electron affinities become less negative from top to bottom of a group.

What is the trend for electron affinity across a period?

Electron affinity increases going left to right across a period. The overall trend across a period occurs because of increased nuclear attraction. Going down the group the electron affinity should decrease since the electron is being added increasingly further away from the atom. Less tightly bound and therefore closer in energy to a free electron.

What is electron affinity and how is It measured?

Electron affinities are difficult to measure. Electron affinity increases going left to right across a period. The overall trend across a period occurs because of increased nuclear attraction. Going down the group the electron affinity should decrease since the electron is being added increasingly further away from the atom.

How does electron affinity change as you go down the group?

Going down the group the electron affinity should decrease since the electron is being added increasingly further away from the atom. Less tightly bound and therefore closer in energy to a free electron.

Why does the attraction between electrons decrease down the periodic table?

As one goes down the period, the shielding effect increases, thus repulsion occurs between the electrons. This is why the attraction between the electron and the nucleus decreases as one goes down the group in the periodic table.