Chemical Reactions and Quantities
Unlock the foundational rules of chemistry by translating formulas, balancing chemical equations, and using the mole to predict reaction quantities with confidence.
Like Duolingo, but for Chemical Reactions and Quantities. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 11 levels across 2 sections, about 22 minutes end to end, roughly 4 days at five minutes a day. It moves through Reading and Balancing Reactions and Quantities and Reaction Math. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in Chemical Reactions and Quantities
- Subscripts show the fixed ratio of atoms bonded inside every single unit
- Changing the amount of liquid changes the total number of molecules, not the ratio inside each molecule
- A missing subscript implicitly means a count of one atom
- Ionic compounds must have a net electrical charge of zero
- Multiple copies of an ion are added until positive and negative charges cancel out
- Equal and opposite charges cancel in a 1-to-1 ratio without extra subscripts
- Covalent compounds share electrons rather than balancing static charges
- Names of covalent molecules use numerical prefixes like mono-, di-, and tri- to tell you the exact count of each atom
- 'Di-' means two atoms of that element are present
- Polyatomic ions are clusters of atoms that travel and react together as one charged package
- Parentheses protect the identity of the cluster before applying an outside multiplier subscript
- Placing a subscript directly next to an existing number multiplies only that single element
- In chemical reactions, atoms only rearrange and are never created or destroyed
- Every single atom in the starting reactants must be accounted for in the final products
- Subscripts define the specific chemical identity of a compound (H2O is water, H2O2 is hydrogen peroxide)
- Coefficients in front change the quantity of molecules without altering what the substance is
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives Chemical Reactions and Quantities the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
In a formula like H₂O, what does the little lowered number 2 tell you?
Get it right to open this lesson and 10 more in the app.
How to learn Chemical Reactions and Quantities, step by step
Go in order. 11 short levels across 2 sections, about 22 minutes in all, five minutes a day.
- 1
Reading and Balancing Reactions
- Decoding Formulas and Compounds
- Balancing Equations Systematically
- 2
Quantities and Reaction Math
- The Mole: Counting by Weighing
- Stoichiometry and Limiting Reactants
2 sections · 4 units · 11 levels. Built to play, not to enroll.
Questions about Chemical Reactions and Quantities
How do I learn Chemical Reactions and Quantities?
Go in order: start with Reading and Balancing Reactions, then Quantities and Reaction Math. On Tomo that's 11 short levels, about 22 minutes in all, played five minutes a day. Start free and play the first level in under a minute.
Is there a Duolingo-style app for Chemical Reactions and Quantities?
Yes. Tomo works like Duolingo: short daily lessons, streaks and quick quizzes. Chemical Reactions and Quantities is one of its free courses, and you can type any other topic to get a course of your own.
Is the Chemical Reactions and Quantities course free?
Yes. Chemical Reactions and Quantities is playable on Tomo's free plan, which doesn't expire. No credit card, no waitlist. Download the app and start your first lesson.
How long does it take to learn Chemical Reactions and Quantities?
11 levels across 2 sections, about 22 minutes of play in total. It's built for five minutes a day, so you finish it a little at a time instead of all at once.
Do I need any background to start Chemical Reactions and Quantities?
No. It's pitched at a beginner level, so it starts where you are and builds up. If you can tap a phone, you can start.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
Chemical Reactions and Quantities is taught in the Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start Chemical Reactions and Quantities today.
Download Tomo, search Chemical Reactions and Quantities, and play your first lesson in under a minute.