Organic Chemistry — Revision Notes

⚡ 30-Second Revision

Formula is not connectivity. Carbon chains, branches and rings support isomerism. Functional groups organise behaviour; homologues commonly differ by CH2, or 14 relative mass units. C3H6 can fit a double-bond structure or a ring. Soap disperses grease through micelles, while hard-water calcium and magnesium can precipitate soap. Organic is not a safety label.

2-Minute Revision

Catenation and tetravalency help explain carbon's structural diversity. Compare the atomic totals in a molecular formula with the connections in a structural formula. C4H10 has straight and branched arrangements; C2H6O can be an alcohol or ether.

A homologous series shares a functional pattern but its members need not have identical physical properties. Attach open-chain and bond-count conditions to general formulas. Soap's structure supports micellar dispersion; hardness can remove useful soap as poorly soluble material.

Natural origin, organic classification and biodegradability answer different questions.

5-Minute Revision

Draw two different connectivities for C4H10, then rotate one drawing and explain why the rotation is not a third structural isomer. Compare ethanol and dimethyl ether using their shared C2H6O totals and different oxygen connections.

Calculate the CH2 mass increment as 14. Next, give two structures compatible with C3H6 and identify the missing information in a formula-only question. Finish by explaining why hard-water scum is not the same process as useful micelle formation and why that distinction cannot alone establish a product's overall environmental performance.

Vyyuha Quick Recall

FCG: Formula counts atoms; Connectivity joins them; Groups help explain behaviour. Check conditions before extending a general rule.