Chemistry
Chemistry from zero, in seven sections: atomic structure, bonding, stoichiometry, oxidation and reduction, acids and bases, energy, rates and equilibrium, and the chemistry of food and the lab. You build every answer yourself on an interactive bench or a step-by-step board, and each one is checked.
254 lessons254 challenges915 quiz questions
- Beginner friendly
Hands-on interactive lessons
Audio narration on every lesson
Quizzes to test your knowledge
Free certificate of completion
Syllabus
Section 1
Atomic StructureDedicated page
Start sectionStartAtoms from zero: what matter is made of, how the model of the atom grew, protons, neutrons and electrons, isotopes, electrons in shells and orbitals, and the periodic table with its trends.Matter and Atoms
5 lessons920Models of the Atom
5 lessons920Inside the Atom
9 lessons1740Electron Arrangement
9 lessons1740The Periodic Table
8 lessons1535Periodic Trends
6 lessons1125Practice Problems
3 lessons3Section 2
Structure and BondingDedicated page
Start sectionStartHow atoms hold together: ions and ionic compounds, covalent bonds and Lewis structures, the shapes of molecules, polarity, the forces between molecules, metals and giant structures, and the functional groups of carbon compounds.Ionic Bonding
7 lessons1330Covalent Bonds
8 lessons1535Shapes of Molecules
6 lessons1125Polarity
6 lessons1125Forces Between Molecules
6 lessons1125Metals and Giant Structures
5 lessons920Functional Groups
7 lessons1330Practice Problems
4 lessons4Section 3
StoichiometryDedicated page
Start sectionStartChemistry by numbers: the mole, molar mass, gases and the ideal gas law, solutions and concentration, balanced equations, mole ratios and the limiting reactant, with exam-style practice problems.The Mole
6 lessons1125Gases
5 lessons920Solutions
6 lessons1125Equations and Mole Ratios
7 lessons1330Limiting Reactant
4 lessons715Practice Problems
13 lessons13Section 4
Oxidation and ReductionDedicated page
Start sectionStartElectrons on the move: oxidation numbers, oxidizing and reducing agents, half-equations, the reactivity of metals, corrosion, electrolysis and cells.Electron Transfer
5 lessons920Redox Reactions
5 lessons920Half-Equations
5 lessons920Metals and Reactivity
5 lessons920Electrochemistry
4 lessons715Practice Problems
3 lessons3Section 5
Acids and BasesDedicated page
Start sectionStartAcids and bases as proton transfer: conjugate pairs, strong and weak acids, the pH scale, neutralization, titration and the acids around us.Acids and Bases
6 lessons1125Strong and Weak
4 lessons715The pH Scale
7 lessons1330Neutralization
6 lessons1125Acids Around Us
4 lessons715Practice Problems
3 lessons3Section 6
Energy, Rates and EquilibriumDedicated page
Start sectionStartEnergy, rates and equilibrium: exothermic and endothermic reactions, energy diagrams, bond energies, heating curves, what makes a reaction fast, and how an equilibrium answers a change.Energy in Reactions
5 lessons920Bond Energies
5 lessons920Changes of State
4 lessons715Rates of Reaction
6 lessons1125Equilibrium
6 lessons1125Changing an Equilibrium
6 lessons1125Practice Problems
3 lessons3Section 7
Food Chemistry and the LabDedicated page
Start sectionStartThe chemistry of food and the lab: carbohydrates, fats, proteins and food energy, then the skills of the laboratory, from making a solution to a titration.Carbohydrates
4 lessons715Fats and Oils
4 lessons715Proteins
4 lessons715Food Energy and Additives
4 lessons715Laboratory Skills
5 lessons920Experiments
4 lessons715Practice Problems
2 lessons2
Learn by Building
Build atoms from protons, neutrons and electrons, fill shells and orbitals, and work on a live periodic table. Every Check names the exact mistake.
Build every atom from protons, neutrons and electrons, and read what the numbers on its symbol mean.
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Stay consistent and watch your progress grow! Track your daily chemistry habit, protect your streak with freeze days, and earn rewards for showing up every day.
12 days streak
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January 2026
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Double or Nothing
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Promotion zoneEvery way to learn
Read, listen, test yourself, ask the AI about your own bench, or look up anything you've already covered. Every lesson meets you where you are.
Everything around you is matter, and all matter is made of tiny particles called atoms.
A substance made of only one kind of atom is an element. There are 118 known elements.
The periodic table lists every element with its symbol: H for hydrogen, O for oxygen.
Earn a Certificate
Earn a certificate when you complete a section. Add it to your LinkedIn profile to show how far your chemistry has come.
Certificate of Completion
Chemistry Atomic Structure
Add to LinkedInWhy learn chemistry with Coddy
- You build the atom. Add protons, neutrons and electrons yourself and watch the element, the mass number and the charge change.
- Every mistake has a name. Two electrons with the same spin, a subshell filled out of order, the wrong element: the check says which.
- The periodic table is a tool, not a poster. Tap, place, order and paint it until its patterns make sense.
- Calculations with units, one step at a time. Mole, gas and solution problems are worked on a board that checks every step, and a missing unit counts as a mistake.
Frequently asked questions about this course
What is chemistry?
The science of matter: what substances are made of, how their atoms are arranged and how they change into other substances. The course starts with the atom, because everything else is built from it.
Do I need to know anything before starting chemistry?
No. The course starts from what everything is made of and adds one idea per lesson. Arithmetic is enough: the third section, Stoichiometry, adds a few simple formulas such as n = m/M, and every calculation is solved in steps on a board.
What does the chemistry course cover?
Seven sections. Atomic Structure, 45 lessons: matter and atoms, models of the atom, protons, neutrons and electrons, ions, isotopes and radioactive decay, electron configurations, the periodic table and periodic trends. Structure and Bonding, 49 lessons: ionic and covalent bonds, Lewis structures, the shapes of molecules, polarity, forces between molecules, metals and giant structures, and functional groups. Stoichiometry, 41 lessons: the mole, gases, solutions, balancing equations, mole ratios and the limiting reactant. Oxidation and Reduction, 27 lessons: oxidation numbers, oxidizing and reducing agents, half-equations, the reactivity of metals, corrosion and electrolysis. Acids and Bases, 30 lessons: proton transfer, strong and weak acids, pH, neutralization and titration. Energy, Rates and Equilibrium, 35 lessons: energy diagrams, bond energies, heating curves, reaction rates, the equilibrium constant and Le Chatelier's principle. Food Chemistry and the Lab, 27 lessons: carbohydrates, fats and proteins, food energy and the skills of the laboratory. Each ends with exam-style practice.
How are the chemistry challenges checked?
Each challenge is solved on an interactive bench: the Atom Builder, the Shell & Orbital Filler, the Periodic Table, the Mass Spectrum, the Lewis Board for drawing molecules, the Equation Balancer, the Ion Combiner, boards for oxidation numbers, pH, energy diagrams and equilibria, or a board for calculations in steps that checks each step and its unit. When something is wrong, the check names the exact mistake, such as the wrong element, a broken Hund's rule, an atom without its octet or a missing unit.
Is the chemistry course free?
Yes, every lesson and challenge is free. Pro removes the daily limit and adds unlimited help from Bugsy, the AI tutor.
Do I get a Chemistry certificate when I finish?
Yes. When you complete the Chemistry course you receive a free certificate of completion that you can share on LinkedIn or add to your resume.
