The two compounds $V$ and $W$ are isomers with molecular formula $\text{C}_4\text{H}_8\text{O}$, and they display the following properties and reactions: each compound reacts with sodium metal, and each decolourises bromine water. Compound $V$ gives a yellow precipitate with alkaline aqueous iodine, but compound $W$ does not. On treatment with cold $\text{KMnO}_4\text{(aq)}$, both $V$ and $W$ form the same neutral compound $X$, $\text{C}_4\text{H}_{10}\text{O}_3$. Both $V$ and $W$ occur as pairs of stereoisomers.
(a(i))
Suggest which functional groups account for the reactions with sodium.
(a(ii))
Suggest which functional groups account for the reactions with bromine water.
(a(iii))[3]
Suggest which functional groups account for the reactions with alkaline aqueous iodine.
(b)[2]
Suggest structures for $V$ and $W$.
(c)[2]
State the type of stereoisomerism shown by compound $V$ and draw the structures of the stereoisomers.
(d)[1]
Suggest the structure of the neutral compound $X$.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Hydroxyl ($\text{-OH}$) groups are present” …