specification overview
Pearson Edexcel International A-Level Chemistry (YCH11) is a modular qualification made up of 6 units, examined in January, June and October. Units 1-3 form the International AS (IAS); units 4-6 add the International A2 for the full IAL. Practical skills are assessed in dedicated exam papers (Unit 3 at IAS, Unit 6 at IAL), not through a separate endorsement.
subject content
1. Structure, Bonding and Introduction to Organic Chemistry
Unit 1 (WCH11)- Atomic structure and the Periodic Table
- Bonding and structure
- Introduction to organic chemistry
2. Energetics, Group Chemistry, Halogenoalkanes and Alcohols
Unit 2 (WCH12)- Energetics
- Group 1, 2 and 7 chemistry
- Halogenoalkanes, alcohols and carbonyl compounds
3. Practical Skills in Chemistry I
Unit 3 (WCH13)- Experimental techniques and procedures from units 1 and 2
- Data analysis and evaluation
4. Rates, Equilibria and Further Organic Chemistry
Unit 4 (WCH14)- Rates of reaction; entropy and Gibbs free energy
- Equilibria (Kc, Kp) and acid-base equilibria
- Further organic chemistry (aromatic, carboxylic acids)
5. Transition Metals and Organic Nitrogen Chemistry
Unit 5 (WCH15)- Redox and transition metal chemistry
- Organic nitrogen chemistry
- Analytical techniques including NMR
6. Practical Skills in Chemistry II
Unit 6 (WCH16)- Experimental techniques and procedures from units 4 and 5
- Advanced data analysis and evaluation
assessment structure
| Paper | What's assessed | Length | Marks | Weight | Question types |
|---|---|---|---|---|---|
| Unit 1 (WCH11) | Structure, Bonding and Introduction to Organic Chemistry | 1h 30m | 80 | 20% IAL / 40% IAS | Multiple-choice, short-open, open-response, calculations and extended writing |
| Unit 2 (WCH12) | Energetics, Group Chemistry, Halogenoalkanes and Alcohols | 1h 30m | 80 | 20% IAL / 40% IAS | Multiple-choice, short-open, open-response, calculations and extended writing |
| Unit 3 (WCH13) | Practical Skills in Chemistry I (units 1-2 techniques) | 1h 20m | 50 | 10% IAL / 20% IAS | Short-open, open-response and calculation questions on practical skills |
| Unit 4 (WCH14) | Rates, Equilibria and Further Organic Chemistry (may include synoptic content from units 1-2) | 1h 45m | 90 | 20% IAL / 40% IA2 | Multiple-choice, short-open, open-response, calculations and extended writing |
| Unit 5 (WCH15) | Transition Metals and Organic Nitrogen Chemistry (may include synoptic content) | 1h 45m | 90 | 20% IAL / 40% IA2 | Multiple-choice, short-open, open-response, calculations and extended writing |
| Unit 6 (WCH16) | Practical Skills in Chemistry II (units 4-5 techniques) | 1h 20m | 50 | 10% IAL / 20% IA2 | Short-open, open-response and calculation questions on practical skills |
The qualification is modular. Papers are available in January, June and October each year, so units can be sat in stages. The IAS is claimed on completion of units 1-3; the full IAL on completion of all six.
assessment objectives
| AO | What it means | Overall |
|---|---|---|
| AO1 | Demonstrate knowledge and understanding of science. | 32-34% |
| AO2(a) | Application of knowledge and understanding of science in familiar and unfamiliar contexts. | 33-36% |
| AO2(b) | Analysis and evaluation of scientific information to make judgements and reach conclusions. | 11-14% |
| AO3 | Experimental skills in science, including analysis and evaluation of data and methods. | 20% |
required practicals
| Practical | What it involves |
|---|---|
| CP1 Measurement of the molar volume of a gas. | – |
| CP2 Determination of the enthalpy change of a reaction using Hess's Law. | – |
| CP3 Finding the concentration of a solution of hydrochloric acid. | – |
| CP4 Preparation of a standard solution from a solid acid and use it to find the concentration of a solution of sodium hydroxide. | – |
| CP5 Investigation of the rates of hydrolysis of some halogenoalkanes. | – |
| CP6 Chlorination of 2-methylpropan-2-ol with concentrated hydrochloric acid. | – |
| CP7 The oxidation of propan-1-ol to produce propanal and propanoic acid. | – |
| CP8 Analysis of some inorganic and organic unknowns. | – |
| CP9 Following the rate of the iodine-propanone reaction by a titrimetric method and investigating a 'clock reaction' (Harcourt-Esson, iodine clock). | – |
| CP10 Finding the activation energy of a reaction. | – |
| CP11 Finding the Ka value for a weak acid. | – |
| CP12 Investigating some electrochemical cells. | – |
| CP13 Carry out redox titrations with both iron(II) ions and potassium manganate(VII), and sodium thiosulfate and iodine. | – |
| CP14 The preparation of a transition metal complex. | – |
| CP15 Analysis of some inorganic and organic unknowns. | – |
| CP16 The preparation of aspirin. | – |
key tips for success
Plan your unit staging early
Papers are available in January, June and October. Decide with your school which units go in which series so you're not cramming five theory units at once.
Prepare specifically for Units 3 and 6
The practical-skills papers are worth 20% of the IAL combined and test techniques from the preceding theory units. Practise experimental design, data analysis and evaluation using unfamiliar contexts.
Expect synoptic questions on Units 4 and 5
Later units can pull knowledge from earlier ones. Revise units 1-2 before sitting units 4 and 5, not just the newer content.
Master organic mechanisms early
Introduced in Unit 1, extended through Unit 4 and Unit 5. Practise nucleophilic substitution, electrophilic addition, aromatic and carbonyl mechanisms with correctly-placed curly arrows.
Interpret spectra
Unit 5 covers NMR spectroscopy. Practise assigning peaks in proton and carbon NMR alongside IR and mass spec, especially in combined-spectra questions.
Know the difference between IAS and IAL
Units 1-3 make up the International Advanced Subsidiary (IAS), a standalone qualification. Adding units 4-6 gives you the full IAL.
Where to next
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