GCSE Chemistry Equations and Formulas to Memorise

June 2026

Unlike Physics, GCSE Chemistry doesn't give you an equation sheet — you're expected to recall the key formulas and apply them. Knowing them cold turns the quantitative questions, which many students fear, into easy marks.

The formulas you must know

• moles = mass ÷ relative formula mass (M_r)
• concentration (g/dm³) = mass ÷ volume
• concentration (mol/dm³) = moles ÷ volume
• percentage yield = (actual yield ÷ theoretical yield) × 100
• atom economy = (M_r of desired product ÷ M_r of all reactants) × 100
• relative formula mass = sum of the relative atomic masses

Don't just memorise — practise applying

Knowing a formula isn't the same as being able to use it under time pressure. Work through past-paper calculation questions, rearrange each formula three ways, and always include units in your answer — unit errors are a common reason students drop marks they had otherwise earned.

Learn balancing and state symbols too

Balancing symbol equations and adding state symbols (s, l, g, aq) are tested constantly. Practise balancing a few equations every day until it becomes automatic — it's a skill that rewards little-and-often practice far more than cramming.

The fastest way to memorise them

Formulas are perfect flashcard material: the prompt on one side, the equation on the other. BrightRevision's flashcards with spaced repetition let you drill every Chemistry formula and revisit the ones you keep forgetting, so they're automatic by exam day.