Ch.8 - Periodic Properties of the ElementsWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

The fourth quantum number, ms, determines the spin of an electron within an atomic orbital. 

The Fourth Quantum Number

Whereas the first 3 quantum numbers describe the atomic orbital where you find the electron, the final quantum number, ms, describes spin the electron possesses. 

Concept #1: Spin Quantum Number Part 1

The Pauli Exclusion Principle implies that two electrons in the same atomic orbital cannot spin in the same direction so as to avoid having the same four quantum numbers. 

Concept #2: Spin Quantum Number Part 2

Example #1: State the electron configuration of boron and list the four quantum numbers of the 1st and the 5th electron.