MYP Chemistry: Chemical Reactions & Word Equations FAQ

Identify reactants and products first, write them in a word equation (reactants → products), then convert to a balanced symbol equation with correct state symbols. Examiners want the arrow direction right, reactants named accurately, and - at MYP 4-5 - the symbol equation balanced with coefficients, not subscripts changed.

A word equation names the reactants and products of a reaction in words rather than chemical formulae, written as reactants → products. It's the first step before writing a balanced symbol equation and is how MYP 4 students are usually introduced to chemical change before formulae are expected.

Count atoms of each element on both sides, then add whole-number coefficients in front of formulae (never change subscripts) until every element balances. Balance metals first, then non-metals, then oxygen and hydrogen last - that order avoids the most common student mistake.

MYP Chemistry typically covers synthesis (combination), decomposition, single displacement and double displacement reactions, alongside combustion as a commonly examined fifth type. Recognising which type you're looking at helps you predict products before you even attempt the word equation.

Equations must balance because of the law of conservation of mass - atoms aren't created or destroyed in a chemical reaction, only rearranged. An unbalanced equation implies matter has appeared or vanished, which is chemically impossible and will lose marks under MYP Criterion A even if the substances named are correct.

The three I see most: writing formulae instead of names in a word equation, using an equals sign instead of an arrow, and forgetting that word equations don't need balancing numbers at all - that's the job of the symbol equation stage. Fix these and most marks come easily.

Yes, from MYP 4 onwards you're generally expected to include state symbols - (s), (l), (g), (aq) - in symbol equations, especially for extended or criterion-based tasks. Leaving them off a fully correct symbol equation can still cost a mark under detailed, accurate scientific communication.

Show every step: word equation, unbalanced symbol equation, then the balanced version with state symbols - don't skip straight to the final answer. Under MYP Criterion A and C, method matters as much as the final equation, so examiners reward visible, logical steps even if your final balance has a small slip.

Reaction and equation questions mostly sit under MYP Criterion A (Knowing and Understanding), assessed through the command terms 'state', 'balance', 'identify' and 'construct'. Longer investigative tasks involving reactions can also draw on Criterion B (Inquiring and Designing) if a practical or data-analysis element is attached.

MYP word equations and balancing are the direct foundation for DP Chemistry's stoichiometry, where you'll use balanced equations to calculate moles, masses and yields. According to the IB, the current DP Chemistry guide had first teaching in 2023 and first exams in 2025, and it assumes fluent equation-balancing from day one - there's no re-teaching of it.

Repetition with immediate feedback works best - a mix of topical worksheets for pure balancing drills and mixed question banks that force students to identify reaction type before writing the equation. Revision Notes with worked examples are useful for a child revising independently without a teacher checking each step.

Balancing equations uses basic arithmetic - ratios and simple multiplication - rather than advanced maths, so a student who's shaky in maths class isn't automatically disadvantaged here. The bigger barrier is usually notation habits (arrows, symbols, states) rather than numerical ability, and those are fixed through targeted practice, not more maths tuition.