Use electron configurations to explain the following observations...

Question

Use electron configurations to explain the following observations: (a) The first ionization energy of phosphorus is greater than that of sulfur. (b) The electron affinity of nitrogen is lower (less negative) than those of both carbon and oxygen. (c) The second ionization energy of oxygen is greater than the first ionization energy of fluorine. (d) The third ionization energy of manganese is greater than those of both chromium and iron.

Accepted Answer

Step 1: Understand the concept of electron configuration and how it relates to ionization energy and electron affinity. Ionization energy is the energy required to remove an electron from an atom, while electron affinity is the energy change when an electron is added to an atom.. Step 2: For part (a), compare the electron configurations of phosphorus (P) and sulfur (S). Phosphorus has the configuration [Ne] 3s² 3p³, and sulfur has [Ne] 3s² 3p⁴. The half-filled p subshell in phosphorus is more stable, making it harder to remove an electron compared to sulfur.. Step 3: For part (b), examine the electron configurations of nitrogen (N), carbon (C), and oxygen (O). Nitrogen has [He] 2s² 2p³, carbon has [He] 2s² 2p², and oxygen has [He] 2s² 2p⁴. The half-filled p subshell in nitrogen is relatively stable, resulting in a lower electron affinity compared to carbon and oxygen.. Step 4: For part (c), consider the electron configurations of oxygen (O) and fluorine (F). Oxygen's configuration is [He] 2s² 2p⁴, and fluorine's is [He] 2s² 2p⁵. The second ionization energy of oxygen involves removing an electron from a positively charged ion, which requires more energy than removing an electron from a neutral fluorine atom.. Step 5: For part (d), analyze the electron configurations of manganese (Mn), chromium (Cr), and iron (Fe). Manganese has [Ar] 3d⁵ 4s², chromium has [Ar] 3d⁵ 4s¹, and iron has [Ar] 3d⁶ 4s². The third ionization energy of manganese involves removing an electron from a half-filled d subshell, which is more stable and requires more energy compared to chromium and iron.