An unbalanced equation appears with reactants on the left and products on the right.
Use the + / − buttons on each compound to change how many molecules react — never edit the formulas themselves.
Every element must have the exact same count on both sides. Green means balanced, red means it still needs work.
Once every element matches, hit Check Balance before the timer runs out. Use the lowest whole-number ratio for full marks!
Speed and accuracy earn up to 3 stars per level. Chain correct answers for a score multiplier!
You did it!