How do I revise for GCSE chemistry?

The two-sided subject (and the half you are probably avoiding)

Chemistry sits exactly between its siblings: biology is mostly recall, physics is mostly calculation, and chemistry is genuinely both. One half of the marks wants accurate knowledge - definitions, reactivity trends, tests and their results, how bonding explains properties. The other half wants fluent calculation: relative masses, moles, concentrations, percentage yield. The two halves need different revision methods, and here is the honest bit: almost everyone quietly over-revises the half they prefer. Students who like the maths drill calculations and skim the content; students who like the content make beautiful flashcards and hope the moles question is kind.

The fix is structural, not motivational: split your chemistry revision explicitly. Some sessions are recall sessions - flashcards, self-quizzing, blurting a topic from memory. Some sessions are calculation sessions - a page of problems, worked and checked. Deciding the session type in advance stops the drift towards the comfortable half, and it means the exam meets a student trained on both of its faces.

The calculation half: do it like maths, because it is maths

Moles, concentrations, masses and yields are not chemistry facts to memorise - they are procedures to automate, and procedures automate the same way times tables did: repetition with feedback. Do calculation questions little and often, always writing the working in full, always checking against a worked solution line by line. The step most students fumble is not the chemistry, it is the rearranging or the unit conversion - which is good news, because those respond to practice fastest.

• Do a short set of calculation questions in most chemistry sessions - five focused problems beat twenty rushed ones.
• Write every step: the formula, the substitution, the rearrangement, the units. Method marks live on those lines, and so does finding your own slips.
• When a solution beats you, redo the same question from scratch a few days later - understanding a solution and producing one are different skills.
• Mix the calculation types once each feels secure, so choosing the method becomes part of the practice.
• Keep the calculator honest: sanity-check answers (a percentage yield over 100 is telling you something).

Balancing equations: make it a reflex

Balancing chemical equations turns up everywhere - as its own marks, inside calculation questions, behind explanations - so fluency here pays interest across the whole paper. It is a pure skill: nobody balances equations by remembering them, everybody balances them by practising them. Do a few most weeks, from simple to horrible, until the count-adjust-recount loop runs without conscious effort. Symbol equations, state symbols if your paper wants them, and (for higher tier) ionic and half equations as your specification requires. Ten minutes a week from now until the exam and this stops being a question type - it becomes free marks with a formula attached.

The periodic table is a tool, not a poster

You will normally have a periodic table in front of you in the exam - check your board's version, and then practise with it, because the papers assume you can use it, not just admire it. Reading off atomic and mass numbers for calculations, placing an unfamiliar element in a group and predicting its behaviour from the trend, reasoning about reactivity from position - these are skills the table enables and the questions test. The trends themselves (what changes down a group, across a period, and why) belong in your recall deck; the fluency of applying them to an element you have never studied comes from doing practice questions with the table open. An element you have never heard of, placed correctly, should feel like information, not ambush.

The recall half: tests, trends and practicals

The knowledge side of chemistry rewards exact recall, so revise it with strict self-testing: definitions word-accurate, tests paired with their positive results (the test and the observation earn together), trends attached to their explanations. Required practicals are on your board's published list, and the questions about them examine understanding of method - variables, fair testing, why each step, what improves accuracy - rather than recitation, so interrogate each one the way you would an experiment you were designing yourself.

Chemistry's explain questions have a particular signature: they want the link chain written out - structure to bonding to property, or position to electron arrangement to reactivity. When you self-test, practise saying the whole chain aloud, because the middle link is the one mark schemes miss you missing.