Master Chemistry from first principles
Atomic structure, bonding, reactions, stoichiometry, gas laws, solutions, and thermochemistry. Aligned to the Massachusetts Curriculum Frameworks for high school Chemistry.
Chemistry — Essential Concepts
Periodic trends, bonding, stoichiometry, gas laws, and acid/base chemistry — every Chemistry Regents essential on one page.
Lab Safety & the Scientific Method
Before you mix anything: master the safety rules and the experimental mindset that every Regents question tests. Hypotheses vs theories, controls, sig figs, and the everyday gear that keeps the lab safe.
Matter: States, Properties, and Why It All Changes
Solid, liquid, gas — and the difference between a physical and chemical change. Mass conservation, mixtures vs pure substances, and the 5 major reaction types every Regents student must recognize on sight.
Reading the Periodic Table: Trends That Predict Everything
The periodic table isn't a list — it's a predictive engine. Groups, periods, blocks, and the four major trends (atomic radius, ionization energy, electronegativity, metallic character) that the Regents leans on heavily.
Atoms: Subatomic Particles & Electron Configuration
Protons, neutrons, electrons — and the rules that govern where electrons live. Isotopes, the Bohr model, modern orbitals, and how to write the configuration of any element you'll see on the Regents.
Chemical Bonding: Ionic, Covalent, and Molecular Shapes
Why do atoms bond at all? Ionic, covalent, and metallic bonding compared — plus Lewis structures, polarity, VSEPR shapes, and the intermolecular forces that make water wet.
The Mole & Stoichiometry: Chemistry's Counting Unit
Avogadro's number is just chemistry's 'dozen' — and stoichiometry is its grocery-list math. Mole conversions, mass-to-mass calculations, limiting reagent, and percent yield with worked examples.
Solutions: Molarity, Dilution, and Colligative Properties
When salt disappears into water, what really happens? Solubility, the math of molarity and dilution, the like-dissolves-like rule, and how dissolved solute changes the boiling and freezing points.
Gas Laws & the Kinetic Molecular Theory
Boyle, Charles, Gay-Lussac, and the ideal gas law — plus the kinetic molecular theory that explains WHY gases behave the way they do.
Thermochemistry: Heat in Reactions
Why some reactions burn hot while others get cold. Endothermic vs exothermic, ΔH sign conventions, specific heat calculations, calorimetry, and phase-change energies.
Nuclear Chemistry: Decay, Fission, and Fusion
Alpha, beta, gamma — the three classic decay types. Half-life problems, balancing nuclear equations, and the difference between fission (splitting heavy nuclei) and fusion (combining light nuclei). Plus how radioisotopes serve medicine and dating.