A-Level Chemistry: Organic Analysis and Synthesis

The analysis topic is where A-level organic chemistry becomes detective work: given spectra and test results, identify the molecule. This quiz assembles the full evidence toolkit the way structure-determination questions deploy it.

The wet-chemistry questions cover the bench tests, made deliberately unambiguous during verification: propanal identified by Tollens' silver mirror and Fehling's brick-red precipitate (with the marginal dichromate option replaced by a cleanly inert one — the kind of precision this collection's review pipeline enforces), and the synthesis-planning question that oxidises propan-1-ol to propanoic acid under reflux.

The spectroscopy questions carry the analytical weight. Mass spectrometry is tested through fragment arithmetic — the loss of 15 from m/z 74 to 59 pointing to a methyl group. Infrared appears as the two-peak logic puzzle: broad O-H plus sharp C=O reading as carboxylic acid. Proton NMR gets the full apparatus: the n+1 splitting rule (a quartet meaning three neighbours), TMS as reference with its twelve equivalent upfield protons, and deuterated chloroform's silence in the proton region. Carbon-13 NMR is covered through environment counting, and the capstone question combines IR and ¹³C evidence to confirm butanone against its C₄H₈O isomers — the genuinely synoptic move.

Chromatography completes the set with the Rf definition.

Each explanation walks the deductive chain from data to structure, which is exactly the skill the structure-determination question rewards. This quiz is the natural final step after Organic I and II in this collection: first learn the reactions, then identify their products.

• Select and interpret bench tests for functional groups
• Read mass spectra through molecular ion and fragment losses
• Interpret IR absorptions and combine them into functional-group conclusions
• Apply proton NMR splitting, integration and reference conventions
• Combine spectra to distinguish isomers and plan synthesis routes

Aligned to the organic analysis content of the DfE A level science subject content: qualitative tests, mass spectrometry, infrared spectroscopy, proton and carbon-13 NMR, chromatography and synthesis planning.