Give the electronic configuration of 1. Al atom and its ion. 2.O atom and its ion.
The Correct Answer and Explanation is:
Correct Answer:
- Aluminum (Al) atom:
Atomic number: 13
Electronic configuration: 1s² 2s² 2p⁶ 3s² 3p¹
Al³⁺ ion:
Electronic configuration: 1s² 2s² 2p⁶
- Oxygen (O) atom:
Atomic number: 8
Electronic configuration: 1s² 2s² 2p⁴
O²⁻ ion:
Electronic configuration: 1s² 2s² 2p⁶
Explanation:
Atoms are made up of protons, neutrons, and electrons. The electronic configuration of an atom describes the distribution of electrons in different energy levels or orbitals around the nucleus. These electrons fill orbitals starting from the lowest energy level to higher ones according to the Aufbau principle.
1. Aluminum (Al):
Aluminum has 13 electrons in its neutral state. These electrons are arranged as follows:
Two electrons fill the first energy level (1s²), eight electrons fill the second energy level (2s² 2p⁶), and the remaining three fill the third energy level (3s² 3p¹). This gives the full configuration of 1s² 2s² 2p⁶ 3s² 3p¹.
When aluminum loses three electrons to form Al³⁺, it loses them from the outermost energy level (the third shell). This results in a stable configuration identical to that of neon, a noble gas. So the Al³⁺ ion has the configuration 1s² 2s² 2p⁶.
2. Oxygen (O):
Oxygen has 8 electrons in its neutral state. Its configuration is:
Two electrons go into the 1s orbital, two into the 2s, and four into the 2p orbitals, giving 1s² 2s² 2p⁴.
Oxygen tends to gain two electrons to achieve a full outer shell like neon. When it gains two electrons, it becomes the O²⁻ ion, and its configuration becomes 1s² 2s² 2p⁶. This configuration shows a stable, full outer shell, which makes the ion more stable than the neutral atom.
