Question 1a
Give the IUPAC names of isomers B and C.
[2]
Question 1b
Question 1c
State the number of 1H NMR signals that would appear in the 1H NMR of propanal and state the ratio of the area under the peaks in which they would appear.
[2]
Give the IUPAC names of isomers B and C.
[2]
State the number of 1H NMR signals that would appear in the 1H NMR of propanal and state the ratio of the area under the peaks in which they would appear.
[2]
State the number of peaks found in the 1H NMR spectrum of glycine.
[1]
c) State the ratio of the areas under the hydrogen peaks for glycine.
[1]
a) Deduce the hydrogen deficiency of but-1-ene.
Using section 26 of the data booklet, state the name of the compound that has produced the spectrum shown.
[1]
a) Geraniol is an organic molecule that contains alkene and alcohol functional groups.
The mass spectrum of geraniol is shown below.
i) State how this mass spectrum can be used to confirm the molar mass of geraniol. [1]
ii) Give the formula of an ion that could be responsible for the peak at m/ z = 69. [1]
Apart from the peaks due to the C—C and C—H bonds, what peak(s) would be present in the infrared spectrum of the distillate.
[1]
Using section 28 of the data booklet, suggest the molecular formulae of the ions responsible for peaks in the mass spectrum with the following m/e values.
i) 15 [1]
ii) 100 [1]
i) Use the mass spectrum to show that the empirical and the molecular formulae of the compound mentioned are the same. [1]
ii) Using section 28 of the data booklet, suggest the species responsible for the peak at m/z = 29. [1]
a) This question is about some isomeric alcohols with the molecular formula C5H12O.
Some alcohols were heated with potassium dichromate(VI) and sulfuric acid. The organic compounds were separated from the reaction mixtures and purified.
The infrared spectra of two of these organic compounds are shown below.
Using section 26 of the data booklet, deduce the type of compound responsible for each spectrum.
Include in your answer references to wavenumbers and their corresponding bonds.
[2]
c) The infrared spectrum a student obtained of an organic molecule which contains carbon, hydrogen and oxygen atoms is shown below.
Use section 26 of the data booklet and information from the infrared spectrum to explain how the student deduced that the spectrum shows the presence of a carbonyl group.
[1]
d) In an experiment to prepare a sample of ethanal, CH3CHO, ethanol, C2H5OH, is reacted with acidified potassium dichromate (VI) and the reaction mixture is distilled. The infrared spectra for ethanol and ethanal are shown below.
i) State the bonds that give rise to the absorption in the ethanol spectrum at 3400 cm-1 and the absorption in the ethanal spectrum at 1720 cm-1. [1]
ii) Explain why the absorption at 3400 cm-1 in the ethanol spectrum does not appear in the spectrum for ethanal. [1]