How Molecules React
Move beyond memorizing reaction types and develop an intuitive mental model for chemical behavior. Learn to map electron flow, distinguish between kinetic speed and thermodynamic stability, and steer reaction outcomes through equilibrium and solvent choice.
Like Duolingo, but for How Molecules React. 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 the Molecular Field and Steering the Reaction. It assumes you already know the basics.
Free forever · No credit card · iPhone & Android
Key ideas in How Molecules React
- Oxygen and halogens pull electron density toward themselves through sigma and pi bonds.
- The atom stripped of electron density develops a partial positive charge that attracts attackers.
- Bonds between atoms of identical electronegativity lack polarized regions for easy attack.
- A nucleophile carries a lone pair or pi bond that it donates to form a new bond.
- An electrophile accepts electrons at an electron-deficient, partially positive atom.
- Arrows trace electrons flowing from electron-dense regions toward electron-depleted regions.
- Resonance contributors represent human drawing limits, not molecules flipping back and forth.
- Delocalized electrons spread across an orbital framework to form a single blended hybrid.
- Both oxygens in acetate continuously share equal, permanent partial negative charges.
- Bulky alkyl groups occupy three-dimensional space around a central carbon atom.
- Steric crowding physically blocks an incoming nucleophile from approaching the electrophilic center.
- Tertiary carbons are heavily shielded compared to accessible methyl and primary carbons.
- Thermodynamic stability dictates if a reaction releases free energy overall
- A huge activation energy barrier can make a favorable reaction unimaginably slow
- Kinetic persistence despite thermodynamic instability is called kinetic trapping
- The transition state is a fleeting geometry poised at the highest energy peak
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 How Molecules React 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.
What happens to a carbon atom when an attached oxygen pulls electron density away from it?
Get it right to open this lesson and 10 more in the app.
Where How Molecules React takes you
- 1
Reading the Molecular Field
- Spotting Where Electrons Flow
- Kinetics Versus Thermodynamics
- 2
Steering the Reaction
- Wrestling Dynamic Equilibrium
- How Solvents Direct Pathways
2 sections · 4 units · 11 levels. Built to play, not to enroll.
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
How Molecules React is taught in the Professor style: clear, structured, thorough. 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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