Compound W has molecular formula C4H10O. It contains only one functional group.

1. (a)(i)Table 5.1 shows the two peaks with the greatest m/e values in the mass spectrum of W. Table 5.1 m/e relative abundance 74 50 75 X Calculate the relative abundance, x, of the peak at m/e = 75 using the information from Table 5.1. x = ............................[1]
2. (a)(ii)The mass spectrum of W also shows peaks at m/e = 29 and m/e = 59. Suggest the molecular formulae of these fragments. m/e = 29 ............................ m/e = 59 ............................[2]
3. (b)(i)A sample of W, C4H10O, is heated under reflux with an excess of acidified K2Cr2O7 until there is no further reaction. Only one organic product, X, is present in the mixture at the end of the reaction. Fig. 5.1 shows the infrared spectrum of W. [Figure 5.1, showing IR spectrum of W] Fig. 5.2 shows the infrared spectrum of X. [Figure 5.2, showing IR spectrum of X] Table 5.2 bond functional groups containing the bond characteristic infrared absorption range (in wavenumbers)/cm-1 C-O hydroxy, ester 1040–1300 C=C aromatic compound, alkene 1500–1680 C=O amide 1640–1690 carbonyl, carboxyl ester 1670–1740 1710–1750 C≡N nitrile 2200–2250 C-H alkane 2850–2950 N-H amine, amide 3300–3500 O-H carboxyl 2500–3000 hydroxy 3200–3650 Absorption A is shown in Fig. 5.1. Absorption B is shown in Fig. 5.2. Complete Table 5.3 using the information given in Fig. 5.1, Fig. 5.2 and Table 5.2. Table 5.3 absorption bond functional group containing the bond A B[1]
4. (b)(ii)Use the information in (a) and (b)(i) to draw the structure of X in the box in Fig. 5.3. + acidified W K2Cr2O7 C4H10O Fig. 5.3 X[1]
5. (c)(i)Y is a structural isomer of W. Both W and Y produce colourless bubbles when sodium is added to them. Y does not react when heated with acidified K2Cr2O7. Y does not react when warmed with alkaline I2(aq). Name the functional group present in Y.[1]
6. (c)(ii)Complete the equation to describe the reaction of W or Y with sodium. ..........C4H10O + ..........Na → ............................[1]
7. (c)(iii)Draw the structure of Y.[1]

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