Part of the Chemistry JourneyBetaJourneyStoichiometry: Moles, Equations and the Limiting Reactant
Six chapters and 41 lessons, from counting particles in moles to reactions on an industrial scale. Every calculation is solved step by step on a board that checks each step and its unit, equations are balanced on the Equation Balancer, and ions are paired on the Ion Combiner.
41 lessons41 challenges115 quiz questions
- Beginner friendly
Hands-on interactive lessons
Quizzes to test your knowledge
Free certificate of completion
Syllabus
This section is part of the Chemistry Journey. The full syllabus has more sections: click any preview below to view it on the Journey page.
- Section 1Atomic Structure45 lessons
- Section 2Structure and Bonding49 lessons
Section 3
Stoichiometry
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 lessons13- Section 4Oxidation and Reduction27 lessons
- Section 5Acids and Bases30 lessons
- Section 6Energy, Rates and Equilibrium35 lessons
- Section 7Food Chemistry and the Lab27 lessons
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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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 CompletionChemistry Atomic Structure
Add to LinkedInWhy learn stoichiometry with Coddy
- Calculations in steps, with units. Write each step on the board, the formula, the numbers and the unit, and a wrong step or a missing unit is caught where it happens, not at the end.
- Equations you balance by hand. Change the coefficients on the Equation Balancer and watch the atoms on each side add up until they match.
- Ions you combine. Pair cations and anions on the Ion Combiner to write the formula of a salt, then work out the concentration of each ion in solution.
- Exam-style practice. The last chapter is multiple choice, multi-part calculation questions and a question on a science article, the way chemistry exams ask them.
Frequently asked questions about stoichiometry
What does the stoichiometry section cover?
The mole, Avogadro's number and molar mass, converting between mass, moles and particles, gases with molar volume, Avogadro's law and the ideal gas law PV = nRT, molar concentration, preparing and diluting solutions and the concentration of ions, balancing equations, mole ratios, mass and gas volume calculations, reactions in solution and precipitation, the limiting reactant and what is left over, and a final chapter of exam-style practice.
What is stoichiometry?
The arithmetic of chemical reactions: how much of each substance reacts and how much product forms. A balanced equation gives the ratio in moles, and moles connect that ratio to the masses, volumes and concentrations you can measure.
How do you solve a stoichiometry problem?
Balance the equation, turn what you are given into moles, use the mole ratio from the equation to find the moles of what you want, then turn those back into grams, liters or a concentration. For example, 4 g of hydrogen is 2 mol, which makes 2 mol of water, or 36 g.
How long is the stoichiometry section?
Six chapters and 41 lessons, each a few minutes long. Finishing it earns a free, verifiable certificate.
What's the fastest way to learn Stoichiometry?
Write Stoichiometry every day. Coddy's course is structured exactly for that: short interactive lessons, immediate exercises, and AI hints when you stall. You spend more time coding Stoichiometry than waiting on long video lectures.
Do I get a Stoichiometry certificate when I finish?
Yes. When you complete the Stoichiometry course you receive a free certificate of completion that you can share on LinkedIn or add to your resume.
