Question

What is electron affinity? ​

Answer 1

Electron affinity (EA) is the energy change when a gaseous atom accepts an electron to become an anion. It generally becomes more negative across the periodic table and less negative from top to bottom within a group. EA is a measurable quantity, unlike the calculated value of electronegativity.

Step-by-step explanation:

Electron affinity (EA) is a term used to describe the energy change that occurs when an electron is added to a gaseous atom, forming an anion (negative ion). This process can either release or absorb energy depending on the element involved. The value of the electron affinity is usually expressed in kilojoules per mole (kJ/mol).

There are observable trends in electron affinity across the periodic table. Generally, electron affinities become more negative as one moves from left to right across the periodic table, which means that atoms tend to gain electrons more readily. Conversely, from top to bottom within a group, the electron affinity becomes less negative, indicating a decreasing likelihood of an atom gaining an electron.

It is important to distinguish electron affinity from electronegativity. While electron affinity is a measurable physical quantity involving the energy released or absorbed when a gas-phase atom acquires an electron, electronegativity refers to how tightly an atom attracts electrons in a bond and is a calculated, dimensionless quantity.

Answer 2

The ability of an atom to accept an electron.

Step-by-step explanation:

Electron affinity is measured by observing the energy change of a substance when an electron is added to it in its neutral gas form. For example, elements that are on the far right of the periodic table (excluding noble gases) are more likely to accept electrons rather than give them up. This is why Fluorine has the highest electron affinity of all atoms on the periodic table.