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Chemistry
worth understanding

Structured lessons from first principles to O-level standard. Practice one question at a time — wrong answers come back until you actually get it.

Start learning free See how it works
50+ questions
4 topics, 3 question types
Wrong answers scheduled to retry
The method

Learn, practise, retain.

A loop that builds genuine long-term recall — not just recognising the answer you saw last night.

01
📖

Read the explanation

Every concept opens with a clear, concise explanation. No textbook walls — just what you need to actually follow the idea before you practise it.

02
⚗️

Answer one question at a time

Multiple choice, fill in the blank, or drag and drop. Each question is answered before you move on — no skipping, no surfing through.

03
🔁

Missed ones come back

Wrong answers get quietly queued for your next session. A concept isn't ticked off until every question has been answered correctly.

In practice

What a session actually looks like

📖 Oxidation States

Assigning oxidation states

Uncombined elements always have oxidation state 0
Oxygen is −2 in most compounds (−1 in peroxides)
Sum of states equals the charge of the species
Hydrogen is +1 except in metal hydrides (−1)
● Medium Multiple choice Q 2 / 5
What is the oxidation state of sulfur in H₂SO₄?
A
+4
B
−2
C
+6
D
0
Built right

What makes it actually useful

🧠

Spaced repetition, built in

Wrong answers don't quietly disappear. They come back in your next session, spaced out the way memory research says works — without you having to set up a single flashcard.

↩ Auto retry
📐

Three question formats

Multiple choice tests whether you recognise the right answer. Fill in the blank tests whether you can recall it cold. Drag and drop tests whether you understand order and sequence.

MC · Fill · Drag
💬

An explanation after every answer

Whether you're right or wrong, you get a clear explanation of why — not just what. That's the bit that actually prevents you from making the same mistake in an exam.

After every question
📈

Starts easy, ends at exam level

Each concept opens at first principles and works through to O-level standard. You're never dropped into the deep end, and you're never stuck at the shallow end either.

Intro → O-Level
What's covered

Topics available now

Redox Chemistry

Oxidation states, half-equations, balancing redox reactions step by step.

O-Level
🔋

Electrochemistry

Electrolysis, electrode potentials, electrochemical cells and feasibility.

O-Level
⚗️

Moles & Calculations

The mole concept, empirical and molecular formulae, stoichiometry.

Intro → O-Level
🧪

Volumetric Analysis

Titration techniques, acid-base calculations, redox titrations with KMnO₄.

O-Level
🔬

Atomic Structure

Electron configuration, subshells, orbital notation and quantum numbers.

Intro → O-Level
🧬

Chemical Bonding

Ionic, covalent, metallic bonding and molecular shapes.

Coming soon
🌡️

Thermochemistry

Enthalpy changes, Hess's law, lattice enthalpy, bond energies.

Coming soon

More on the way

New units added as the curriculum expands.

Ready to start?

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