Common Laws

Law of Conservation of Mass

In a reaction, mass is neither created nor destroyed.

Law of Definite Proportions

Compounds always contain the same elements in the same fixed ratio by mass.

Law of Multiple Proportions

If two elements form multiple compounds, the ratio of masses of the second element combining with a fixed mass of the first element is a simple whole-number ratio.

Dalton’s Atomic Theory

Expands on the previous fundamental ideas.

Boyles Law

At constant temperature and moles, Pressure is inversely proportional to Volume.

Charles Law

Volume and temperature are directly proportional. Assuming constant variables.

Gay-Lussac’s Law

Pressure and temperature are directly proportional. Assuming constant variables.

Avogadro’s Law

Equal volumes of gases at the same temperature and pressure have equal moles (or particles).

Ideal Gas Law

PV = nRT

Kinetic Molecular Theory

Explains gas behavior (pressure, effusion) based on particle motion.

Graham’s Law

Relates gas effusion/diffusion rate to molar mass.

Henry’s Law

Solubility of a gas in a liquid is proportional to its partial pressure.

( c = kP)

Laws of Thermodynamics

Energy conservation, entropy increase.

Hess’s Law

Enthalpy changes are additive for reactions.

Gibbs Free Energy

Predicts spontaneity (Delta G = Delta H - T Delta S).

Law of Mass Action

Equilibrium constant expressions (K).

Raoult’s Law

Vapor pressure of solutions related to mole fraction.

Colligative Properties

Boiling point elevation, freezing point depression, osmotic presure.

Pauli Exclusion Principle

No two electrons in an atom have identical quantum numbers.

Hund’s Rule

Electrons fill orbitals singly before pairing.

Beer-Lambert Law

Relates absorbance to concentration and path length.

Faraday’s Laws

Relate electrolysis to chare/moles of substance.