Organic Analysis (AQA A Level Chemistry)

Which of the following compounds would form an orange-red precipitate when heated with Fehling’s solution?

Which alcohol is not likely to have a fragment ion at m/z at 43 in its mass spectrum?

Butanal, CH₃CH₂CH₂CHO, and butanone, CH₃CH₂COCH₃, are carbonyl compounds.

When these compounds are compared using analytical methods, which of the following statements is not correct?

Bromine exists as two isotopes ⁷⁹Br and ⁸¹Br, which are found in almost equal abundance.

Which of the following statements is correct?

Which compound is shown in the infrared spectrum below?

Which pair of compounds would you expect to both have a singly charged peak at m/z = 29 in the mass spectrum?

Which compound below does not contain the functional group shown by the infrared spectrum?

Which of the ketones listed would not be expected to have a peak in its mass spectrum at m/z = 57?

Crotonaldehyde, CH₃CH=CHCHO, occurs in soybean oils and can be formed from its alcohol.

Other than the alcohol of crotonaldehyde, what reagents and experimental conditions are needed for producing crotonaldehyde?

Calcium iodide is reacted with silver nitrate and a yellow coloured precipitate is produced.

Which pair of responses helps to confirm the identity of the anion?

Mixture F is produced upon refluxing compound G with aqueous sodium hydroxide.

Upon distillation of F with acidified potassium dichromate(VI), propanone is produced. Mixing G with aqueous silver nitrate and dilute nitric acid gives a cream precipitate.

What is the identity of compound G?

When the apparatus below was used with compound E, a brick-red precipitate formed in the right-hand tube.

Which compound could be E?

An alcohol can be prepared by hydrolysing the halogenoalkane C₄H₇CHClCH₃ with aqueous sodium hydroxide.

The infrared spectrum for C₄H₇CHClCH₃ is shown in with the C–Cl bond absorption is labelled.

How will the infra-red spectroscopy change as a result of the above reaction?

The mass spectra of three compounds A, B and C are shown below.

Which of the following features of the three compounds A, B and C shows the molecular formula is C₄H₁₀O?

The infrared spectrum of an unknown compound is shown below.

Which compound could have produced the infrared spectrum?

A compound XF_n is a fluoride of another halogen, X, and it is known that n > 1. The highest mass peak in the spectrum of XF_n is the parent ion and has a single peak at m/z = 222.

Which of the following statements is incorrect?

A sample is analysed by mass spectrometry and infrared spectroscopy. The following incomplete data is obtained.

Which of the following compounds could be present in the sample?

Which of the following isomeric alcohols, with molecular formula C₅H₁₂O, cannot be oxidised by acidified potassium dichromate?

In mass spectrometry, which compound forms a molecular ion with a different precise molecular mass from the other three compounds?

This question is about the reaction between cyclopropanone and an excess of methanol which forms a hemiketal compound as shown below.

Which infra-red absorption would the products not produce?