Retort Lane Equations

Balance real school chemical equations on lab-notebook paper and watch every atom row turn green.

Retort Lane Equations is a calm educational puzzle game built around the equations you meet in chemistry class. Each puzzle lays out the reactants and products with a whole-number stepper in front of every substance. Nudge the coefficients up and down, and a live atom tally counts each element on the left and right side. When the counts match, that row turns green. Turn every row green and the equation is balanced.

HOW IT PLAYS
- Set a whole-number coefficient in front of each reactant and product.
- Watch the live tally compare left and right counts for every element.
- Earn three stars only for the lowest whole-number set, found without a hint.
- Stuck? A hint reveals one coefficient, taken from an exact rational solver, so every equation has one true lowest answer.
- Switch on the optional ions-as-units mode to count polyatomic ions such as sulfate as single units when they stay intact, handy for swap reactions.

WHAT'S INSIDE
- 140 classic school equations across six topics: synthesis, decomposition, combustion, single and double replacement, and polyatomic ions.
- Every equation is validated when the app starts, so each puzzle is guaranteed to balance.
- Five tabs: Balance, Topics, Stats, How and Awards.
- Progress, stats and awards are saved on your device.

QUIET BY DESIGN
Retort Lane Equations is fully offline and needs no internet connection. There are no ads, no sign-in and no sound, just grid paper, ink-blue coefficients and the satisfying moment when the last atom row turns green.

Great for students practising for a chemistry test, or anyone who enjoys a tidy logic puzzle.