CHM1011 Study Guide - Quiz Guide: Pauli Exclusion Principle, Electron Affinity, Periodic Trends

• School: Monash University
• Department: Science - Chemistry
• Course: CHM1011
• Professor: Various

Document Summary

Mendeleev discovered that the properties of elements could be predicted based on their arrangement in the periodic table. Elements with the same number of valence electrons (same group) displayed similar properties. Ground state: lowest possible energy state for a set of electrons. Degenerate: a set of orbitals with the same energy. When filling a degenerate set of orbitals in the ground state, pairing of electrons cannot occur until each orbital in the set contains an electron. Single electrons in degenerate orbitals have parallel spins. No two electrons can have the same four quantum numbers. Therefore, each pair of electrons must have opposite spins in order to have different ms numbers. When constructing electron configurations, electrons must be placed in the lowest possible energy level. Electrons are grouped into subshells (electrons which have the same n and l numbers) E. g. if n=2 and l=1, subshell= 2p. A superscript number indicates the number of electrons occupying the subshell.