CHE 131 Chapter Notes - Chapter 8: Aufbau Principle, Transition Metal, Ionic Radius

• School: Stony Brook University
• Department: Chemistry
• Course: CHE 131
• Professor: Troy Wolfskill

Document Summary

Summary of chapter 8- electron configuration and chemical periodicity. Identifying electrons in many-electron atoms requires four quantum numbers: three (n, l: describe the orbital, and a fourth (ms) describes the electron"s spin. The exclusion principle requires each electron to have a unique set of four quantum numbers, therefore, an orbital can hold no more than 2 electrons, and their spins must be paired (opposite) Electrostatic interactions determine sublevel energies as follows : Greater nuclear charge lowels sublevel energy, making electrons harder to. Electron-electron repulsions raise sublevel energy, making electrons easier to remove remove. Repulsions shield electrons from the full nuclear charge, reducing it to an effective nuclear charge, zeff. Penetration makes an electron harder to remove bc nuclear attraction increases and shielding decreases. As a result, an energy level is split into sublevels with the energy order, s < p < d < f. The elements of a group have similar outer electron configurations and similar chemical.