C2 Calculations and Electrochemistry
Moles, equations, concentration, titration, yield, atom economy, electrolysis and electrochemical cells.
How to study for CCEA GCSE Double Award Science
Build each scientific explanation from a model or relationship, show quantitative working, and connect every practical claim to controlled evidence and evaluation.
Core concepts
Concept 1
The mole links mass to relative formula mass and balanced equations provide the reacting mole ratio.
Exam cue: Identify the scientific model, relationship or practical evidence required by the command word.
Concept 2
Percentage yield compares actual with theoretical product while atom economy measures reactant atoms incorporated into the desired product.
Exam cue: Show the mole pathway and equation ratio; for electrolysis, name the ion, electrode and electron change.
Concept 3
Electrolysis moves ions to oppositely charged electrodes where electron transfer produces discharge products.
Exam cue: Use the current CCEA specification formatting and entered tier to decide whether Higher-only detail applies.
Risk pitfalls and guardrails
Using mass ratios directly where the balanced equation gives a mole ratio or reversing anode and cathode.
Guardrail: Do not import another board or science route, omit units from a calculation, or make a scientific claim beyond the stated evidence.
Giving a remembered fact without connecting it to the stated data, observation or scenario.
Guardrail: Do not import another board or science route, omit units from a calculation, or make a scientific claim beyond the stated evidence.
Importing content or paper structure from a separate-science or non-CCEA specification.
Guardrail: Do not import another board or science route, omit units from a calculation, or make a scientific claim beyond the stated evidence.
Memory anchors
Mole
Amount containing the Avogadro number of specified particles.
Molar mass
Mass of one mole of a substance.
Percentage yield
Actual product divided by theoretical product times 100.
Atom economy
Percentage of reactant atoms incorporated into the desired product.
Electrolysis
Decomposition of an ionic substance using electrical energy.
Cathode
Negative electrode where positive ions gain electrons.
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
What is one mole?
How many moles are in 10 g calcium carbonate, Mr=100?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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