Name, or describe in detail, a suitable substance for each of the two phases: the stationary phase and the mobile phase.
Explain what is meant by retention time.
Calculate the percentage of B in the mixture. Show your working.
Complete Table 9.1 with the number of peaks in the carbon-13 NMR spectrum for each of the five isomers of $\text{C}_5\text{H}_{10}\text{O}_2$ that contain an ester group.
State the number of peaks that would appear in the proton ($^1\text{H}$) NMR spectrum of methyl butanoate, $\text{CH}_3\text{CH}_2\text{CH}_2\text{CO}_2\text{CH}_3$. Name all of the splitting patterns observed in this spectrum.
Deduce the structures of the two esters D and E, then draw their displayed formulae in the boxes below.
The spectrum of D shows a quartet at $\delta = 4.1$. On your structure in (i), identify the protons that give rise to this quartet by labelling them F. Explain why the peak is split into a quartet.
The spectrum of E shows a doublet at $\delta = 1.1$. On your structure in (i), identify the protons that produce this doublet by labelling them G. Explain why the chemical shift is 1.1.
Deduce the structures of the two esters D and E, then draw their displayed formulae in the boxes below. D: molecular formula $\text{C}_5\text{H}_{10}\text{O}_2$ E: molecular formula $\text{C}_5\text{H}_{10}\text{O}_2$
The spectrum of D includes a quartet at $\delta 4.1$. Identify the protons responsible for this quartet on your structure in (i) by labelling these protons with the letter F. Explain why this peak is split into a quartet.
The spectrum of E shows a doublet at $\delta 1.1$. Identify the protons responsible for this doublet on your structure in (i) by labelling these protons with the letter G. Explain why this peak has a chemical shift of $1.1$.