1) A bottle containing an unknown organic compound was examined in a university laboratory. There was an incomplete label on the bottle that gave only the empirical formula for the contents: CH₄N. A chemist hypothesised that the unknown compound was 1,2-ethanediamine,
NH₂CH₂CH₂NH₂. Mass spectrometry produced the following spectral data.

i. On the diagram above, identify the base peak.

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ii. At what m/z ratio is the principal peak that supports the chemist’s hypothesis that the unknown compound has the formula
NH₂CH₂CH₂NH₂? Justify your answer.

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iii. Write the semi-structural formula of the species that produces the peak at 30 m/z

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Infrared (IR) spectroscopy was also used to analyse the sample. The spectrum is shown below.

Is this spectrum consistent with the unknown compound being
NH₂CH₂CH₂NH₂? Use evidence from the IR spectrum in your response.

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The sample was also analysed using ¹³C NMR. The spectrum is shown below.

Is the ¹³C NMR spectrum consistent with the structure of
NH₂CH₂CH₂NH₂? Justify your answer.

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