Apply IUPAC rules to state the name of this molecule.

Deduce the structural formula of two isomers of the molecule above with the same functional group.

Describe, using an equation, the oxidation by acidified potassium dichromate(VI) of the substance shown in the diagram. Use the symbol [O] to represent the oxidizing agent.

butan-2-ol/2-butanol;

\({\text{C}}{{\text{H}}_{\text{3}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{OH}}\);

\({{\text{(C}}{{\text{H}}_{\text{3}}}{\text{)}}_{\text{2}}}{\text{CHC}}{{\text{H}}_{\text{2}}}{\text{OH}}\);

\({{\text{(C}}{{\text{H}}_{\text{3}}}{\text{)}}_{\text{3}}}{\text{COH}}\);

Accept condensed or full structural formulas.

Penalise missing H atoms or incorrect bonds (such as C–HO, C–H₂C) only once in the whole paper.

\({{\text{C}}_2}{{\text{H}}_5}{\text{CHOHC}}{{\text{H}}_{\text{3}}} + {\text{[O]}} \to {{\text{C}}_{\text{2}}}{{\text{H}}_{\text{5}}}{\text{COC}}{{\text{H}}_{\text{3}}} + {{\text{H}}_{\text{2}}}{\text{O}}\);

Accept condensed or full structural formulas.

Accept [O] on top of the arrow.

Do not accept equation without H₂O.

Do not accept equation with H⁺/Cr₂O₇^2–.

Most candidates gave the correct name, though often but-2-anol was given.

The question was fairly well answered, though a common error was drawing butan-2-ol in different layouts.

Almost universally unsuccessful. Most students did not follow the instructions and did not use [O] for the oxidizing agent, and the few who did, did not give water as the other product.