Chemistry Cheat Sheet
Your complete reference for first-year university chemistry. From atomic structure and chemical bonding to acids, bases, and electrochemistry — all the formulas and concepts you need to succeed.
Atomic Structure
4 topics
Atomic Theory
The development of atomic models from Dalton to the quantum mechanical model.
Quantum Numbers
The four quantum numbers that describe the state of an electron in an atom.
Electron Configuration
How electrons are arranged in atomic orbitals following the aufbau principle.
Periodic Trends
Patterns in atomic radius, ionization energy, electronegativity, and electron affinity.
Chemical Bonding
5 topics
Ionic Bonding
Formation of ionic compounds through electron transfer between metals and nonmetals.
Covalent Bonding
Sharing of electrons between atoms to form molecular compounds.
Lewis Structures
Representing molecular structure with electron dots and lines for bonds.
VSEPR Theory
Predicting molecular geometry using Valence Shell Electron Pair Repulsion.
Molecular Orbital Theory
Understanding bonding through the combination of atomic orbitals into molecular orbitals.
Stoichiometry
5 topics
The Mole Concept
Avogadro's number and converting between moles, mass, and particles.
Balancing Chemical Equations
Applying the law of conservation of mass to balance chemical reactions.
Limiting Reagents
Identifying the reactant that limits product formation and calculating excess.
Percent Yield
Comparing actual yield to theoretical yield in chemical reactions.
Empirical and Molecular Formulas
Determining chemical formulas from composition data and molar mass.
States of Matter
4 topics
Gas Laws
Boyle's, Charles's, Gay-Lussac's, and combined gas laws.
Ideal Gas Law
PV = nRT and its applications to gas calculations.
Kinetic Molecular Theory
The behavior of gas particles and the assumptions of the kinetic theory.
Phase Diagrams
Understanding phase transitions and critical points using P-T diagrams.
Solutions
3 topics
Concentration Units
Molarity, molality, mole fraction, and percent composition of solutions.
Solubility
Factors affecting solubility and solubility rules for ionic compounds.
Colligative Properties
Vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure.
Thermochemistry
4 topics
Enthalpy
Heat changes in chemical reactions, enthalpy of formation, and reaction.
Hess's Law
Calculating enthalpy changes using the additivity of reaction enthalpies.
Calorimetry
Measuring heat transfer using calorimeters and specific heat capacity.
Bond Energies
Estimating enthalpy changes from bond breaking and bond forming.
Chemical Kinetics
4 topics
Reaction Rates
Measuring and expressing the speed of chemical reactions.
Rate Laws
Determining rate constants and reaction orders from experimental data.
Activation Energy
The Arrhenius equation and the energy barrier for reactions.
Catalysis
How catalysts speed up reactions without being consumed.
Chemical Equilibrium
3 topics
Equilibrium Constants
Kc, Kp, and the relationship between equilibrium concentrations.
Le Chatelier's Principle
Predicting how systems respond to changes in concentration, pressure, and temperature.
ICE Tables
Using Initial-Change-Equilibrium tables to solve equilibrium problems.
Acids & Bases
4 topics
pH and pOH
The pH scale, hydrogen ion concentration, and the relationship between pH and pOH.
Strong vs Weak Acids and Bases
Distinguishing between strong and weak acids/bases and calculating Ka and Kb.
Buffers
How buffer solutions resist pH changes and the Henderson-Hasselbalch equation.
Titrations
Acid-base titration curves, equivalence points, and indicator selection.
Electrochemistry
4 topics
Oxidation-Reduction Reactions
Identifying oxidation states, oxidizing and reducing agents, and balancing redox equations.
Galvanic Cells
How electrochemical cells convert chemical energy to electrical energy.
Standard Reduction Potentials
Using E° values to predict spontaneity and calculate cell potentials.
Electrolysis
Using electrical energy to drive non-spontaneous reactions and Faraday's laws.
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