Chemistry 9701 · AS & A Level · Analytical techniques

Analytical techniques — practice question

Fig. 7.1 shows four esters, $A$, $B$, $C$ and $D$, each with molecular formula $\text{C}_6\text{H}_{12}\text{O}_2$.
(a)[1]

Give the systematic name for ester $A$.

(b(i))[1]

State what retention time means.

(b(ii))[1]

Calculate the percentage by mass of ester $D$ in the original mixture.

(c(i))[2]

Complete Table 7.1 so that it shows the number of peaks in each NMR spectrum for esters $B$ and $C$.

(c(ii))[1]

Identify all of the esters from $A$, $B$, $C$ and $D$ that have at least one triplet peak in their proton ($^1\text{H}$) NMR spectrum.

(d)[6]

Compound F, $\text{C}_6\text{H}_8\text{O}_3$, displays stereoisomerism and effervesces with $\text{Na}_2\text{CO}_3(\text{aq})$. Compound F reacts with alkaline $\text{I}_2(\text{aq})$ to give yellow precipitate G and compound H. Compound F reacts with $\text{LiAlH}_4$ to form compound J, $\text{C}_6\text{H}_{12}\text{O}_2$. Compound F reacts with $\text{SOCl}_2$ to form compound K, $\text{C}_6\text{H}_7\text{O}_2\text{Cl}$. Compound K reacts with propan-2-ol to form compound L. Draw the structures of compounds F, G, H, J, K and L in the boxes in Fig. 7.3.

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