What is the relationship between the ionization energy of a singly charged anion such as Cl^- and the electron affinity of the neutral atom?

Verified step by step guidance

1. Understand that ionization energy is the energy required to remove an electron from an atom or ion, while electron affinity is the energy change when an electron is added to a neutral atom.
2. Recognize that for a singly charged anion like Cl^-, ionization energy refers to the energy needed to remove the extra electron, converting it back to a neutral atom.
3. Note that the electron affinity of a neutral atom, such as Cl, is the energy released when an electron is added to form the anion Cl^-.
4. Realize that the ionization energy of Cl^- is numerically equal to the negative of the electron affinity of Cl, because the processes are essentially the reverse of each other.
5. Conclude that the relationship between the ionization energy of Cl^- and the electron affinity of Cl is that they are equal in magnitude but opposite in sign.

Key Concepts

Ionization Energy

Ionization energy is the energy required to remove an electron from a gaseous atom or ion. For anions, such as Cl^-, the ionization energy reflects the stability of the extra electron. A higher ionization energy indicates that the electron is held more tightly, making it more difficult to remove.

Electron Affinity

Electron affinity is the energy change that occurs when an electron is added to a neutral atom in the gas phase. It quantifies how much energy is released or absorbed when an atom gains an electron. A more negative electron affinity means that the atom more readily accepts an electron, contributing to the formation of anions.

Relationship Between Ionization Energy and Electron Affinity

The relationship between ionization energy and electron affinity is crucial in understanding anion stability. For a singly charged anion like Cl^-, the ionization energy is typically lower than the electron affinity of the neutral atom. This indicates that while the atom can easily gain an electron (high electron affinity), removing that electron from the anion requires a significant amount of energy.