Identify two ions that have the following ground-state electron configurations: (a) [Ar]

Verified step by step guidance

1. Step 1: Understand that the electron configuration [Ar] represents the electron configuration of the noble gas Argon, which has 18 electrons.
2. Step 2: Recognize that ions are formed by the gain or loss of electrons from a neutral atom, resulting in a positive or negative charge.
3. Step 3: Identify that a cation (positively charged ion) with the electron configuration [Ar] would have lost electrons to achieve this configuration. For example, a potassium ion (K⁺) loses one electron from its neutral state (which is [Ar]4s¹) to become [Ar].
4. Step 4: Identify that an anion (negatively charged ion) with the electron configuration [Ar] would have gained electrons to achieve this configuration. For example, a chloride ion (Cl⁻) gains one electron from its neutral state (which is [Ne]3s²3p⁵) to become [Ar].
5. Step 5: Conclude that the ions with the electron configuration [Ar] are K⁺ and Cl⁻, as they have either lost or gained electrons to match the electron configuration of Argon.

Key Concepts

Electron Configuration

Electron configuration describes the distribution of electrons in an atom's orbitals. It is represented using a notation that indicates the energy levels and sublevels occupied by electrons. For example, the notation [Ar] signifies that the electron configuration corresponds to that of argon, which has a complete outer shell, indicating a stable electronic state.

Ionic Charge

Ionic charge refers to the electrical charge that an atom acquires when it loses or gains electrons to achieve a stable electron configuration. Cations are positively charged ions formed by the loss of electrons, while anions are negatively charged ions formed by the gain of electrons. Understanding the ionic charge is essential for identifying ions with specific electron configurations.

Noble Gas Stability

Noble gases, such as argon, are known for their stability due to having a full valence shell of electrons. This stability makes them less reactive compared to other elements. When identifying ions with the electron configuration [Ar], it is important to recognize that these ions achieve a similar stable configuration by either losing or gaining electrons, mimicking the electron arrangement of noble gases.