Advanced Organic Synthesis & Purification Labs for H2 Chemistry Paper 4

Study guide17 Nov 2025, 00:00 ZUpdated 17 Jul 2026

Reviewed by

Azmi·Senior Chemistry Specialist

Q: What does Advanced Organic Synthesis & Purification cover?
A: Step-by-step Paper 4 workflows for reflux, distillation, liquid-liquid extraction, recrystallisation, chromatography, and yield tracking-plus ACE commentary frameworks grounded in SEAB's 2026 H2 Chemistry syllabus.

TL;DR
Organic tasks combine synthetic precision with safety discipline.
Control heating, phase separations, drying, and purity calculations so you can justify every observation and improvement during Paper 4.

Quick organic-practical map

Make, separate, purify, check: Identify the product and main impurity.
Each apparatus choice has a job: Use reflux, distillation, extraction, or recrystallisation for the right step.
Yield and purity need evidence: Record mass, melting point, TLC, or boiling range clearly.

Concrete example: Reflux to complete the reaction, extract the organic layer, dry it with an anhydrous salt, purify by recrystallisation or distillation, then check purity by melting point or TLC.

Keep this workflow with the rest of your Paper 4 drills in our H2 Chemistry Experiments hub.

Status: SEAB's current H2 Chemistry (9476) syllabus PDF is labelled for 2026, and the 9476/04 specimen paper is labelled for examination from 2026. Paper 4 is 2 h 30 min, 50 marks, weighted at 20% with Planning at 4% and MMO/PDO/ACE at 16% combined; simple organic synthesis and purification stay listed in the practical scope.

Code note: 2026 resources use 9476; older notes may still reference 9729.

Quick win box

Focus now: Organic practical focus.
High-yield priority: Separation purity + yield tracking.
60-minute drill: 20 min workflow map · 20 min yield/purity drill · 20 min error correction notes.

1 | Organic investigations in the 2026 syllabus

Sources

Add Eclat Institute as a Preferred Source on Google.

Practise this in a lab

Compare current lesson timings, pricing, and venues for the practical programme that matches this guide.

View H2 Chemistry Practicals (Labs & Experiments)

Practical course record and certificate note

Eclat keeps centre-held attendance records and may issue an internal attendance or completion document based on participation and internal assessment.

For SEAB private-candidate declarations, the centre record is the key evidence. Any Eclat completion document is not an MOE or SEAB qualification or accreditation.

Stage	Mass / g	Observation	Notes
Starting material	2.50	White crystalline solid	Dried at 60 °C prior to weighing.
Crude product (post work-up)	2.10	Pale yellow oil	Stored over anhydrous MgSO₄ overnight.
Purified product	1.60	Colourless crystals	Recrystallised from ethanol.
Theoretical yield	1.85	-	Based on limiting reagent (2.50 g, 0.020 mol).
% yield	86.5	-	`=Purified/Theoretical*100`; uncertainty ±2%.
Melting point (°C)	78.5-79.2	Consistent with literature (79.0)	Capillary method, corrected thermometer.
TLC $R_f$ (product)	0.42	Single spot under UV	Solvent: ethyl acetate:hexane (1:3).

Advanced Organic Synthesis & Purification Labs for H2 Chemistry Paper 4

Quick organic-practical map

Quick win box

1 | Organic investigations in the 2026 syllabus

Sources

Practise this in a lab

2 | Reflux & distillation mastery

3 | Liquid-liquid extraction & drying agents

4 | Recrystallisation & chromatography essentials

4.1 Structural checkpoints (2D)

5 | PDO yield and purity tables

6 | ACE commentary frameworks

7 | Quick readiness checklist

8 | Extend your organic toolkit

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