Formulae, Quantitative Chemistry and Redox
Construct equations, calculate chemical quantities and track oxidation, reduction and electron transfer.
How to prepare for the current ESAT
Confirm your course combination, build no-calculator fluency from Mathematics 1 upward, and use official Pearson materials for authentic timing and interface rehearsal.
Core concepts
Concept 1
Balance full, ionic and half-equations and reason about reversible equilibrium shifts.
Exam cue: Balance atoms and charge before using a mole ratio.
Concept 2
Use moles, masses, formulae, gas volumes, solutions, titrations and percentage yield.
Exam cue: Convert the given quantity to moles, apply the ratio, then convert to the target.
Concept 3
Assign oxidation states and identify oxidation, reduction, agents and disproportionation.
Exam cue: Track electron loss and gain explicitly.
Risk pitfalls and guardrails
Using equation coefficients as mass ratios.
Guardrail: Do not use calculator-dependent shortcuts, import a fact outside the annual specification or overlook a unit, sign, scale or course-module boundary.
Dividing by concentration before converting volume to dm³.
Guardrail: Do not use calculator-dependent shortcuts, import a fact outside the annual specification or overlook a unit, sign, scale or course-module boundary.
Calling oxygen transfer the only definition of redox.
Guardrail: Do not use calculator-dependent shortcuts, import a fact outside the annual specification or overlook a unit, sign, scale or course-module boundary.
Memory anchors
Equation first
A balanced equation supplies the reacting mole ratio.
Moles from mass
n = m/Mᵣ.
Gas at rtp
Use the stated molar volume, commonly 24 dm³ mol⁻¹.
Solution concentration
c = n/V with volume in dm³.
OIL RIG
Oxidation is loss; reduction is gain of electrons.
Agent
An oxidising agent is reduced; a reducing agent is oxidised.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
Balance: __Al + __O₂ → __Al₂O₃.
Formula of magnesium chloride?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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