Determining structures from analytical dataEdexcel International A Level Chemistry: Mind map

Exam questions on Determining structures from analytical data

1. Compound X contains only carbon, hydrogen and oxygen. Combustion analysis shows that it contains 54.5% carbon and 9.1% hydrogen by mass. The mass spectrum of X has its molecular ion peak at m/z 88.
   The infrared spectrum of X has a broad absorption between 2500 and 3300 cm⁻¹ and a strong absorption at 1710 cm⁻¹. State what this shows about the functional group in X.2 marks
2. Compound Y has molecular formula C₃H₆O. Its mass spectrum has a molecular ion peak at m/z 58 and a base peak at m/z 43. Y forms an orange precipitate with 2,4-dinitrophenylhydrazine but gives no silver mirror with Tollens' reagent.
   State how many peaks there are in the ¹³C NMR spectrum of Y, and explain your answer.2 marks
3. Compound Z contains only carbon, hydrogen and oxygen, and its molecular ion peak is at m/z 74. Complete combustion of 0.370 g of Z gives 0.660 g of carbon dioxide and 0.270 g of water.
   Calculate the empirical formula of Z.3 marks