Four esters, A, B, C and D, with the molecular formula C₆H₁₂O₂ are shown in Fig. 7.1. [Figure 7.1]

1. (a)Give the systematic name of ester A.[1]
2. (b)(i)A mixture of these esters, A, B, C and D, is analysed by gas-liquid chromatography. The chromatogram produced is shown in Fig. 7.2. The number above each peak represents the area under the peak. The area under each peak is proportional to the mass of the respective ester in the mixture. [Figure 7.2] State what is meant by retention time.[1]
3. (b)(ii)Calculate the percentage by mass of ester D in the original mixture. percentage by mass of ester D = %[1]
4. (c)(i)Separate samples of the esters, A, B, C and D, are analysed using proton (¹H) NMR and carbon-13 NMR spectroscopy. Complete Table 7.1 to show the number of peaks in each NMR spectrum for esters B and C. [Table 7.1][2]
5. (c)(ii)Identify all of the esters from A, B, C and D that have at least one triplet peak in their proton (¹H) NMR spectrum.[1]
6. (d)Compound F, C₆H₈O₃, shows stereoisomerism and effervesces with Na₂CO₃(aq). Compound F reacts with alkaline I₂(aq) to form yellow precipitate G and compound H. Compound F reacts with LiAlH₄ to form compound J, C₆H₁₂O₂. Compound F reacts with SOCl₂ to form compound K, C₆H₇O₂Cl. 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. [Figure 7.3][6]

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