The diagram shows the mass spectrum of an organic compound - HSC - SSCE Chemistry - Question 4 - 2019 - Paper 1

The peak at m/z 60 likely represents the molecular weight of the organic compound. This information is crucial for identifying the compound from the given options.

We will now analyze the options based on their molecular weights:

• Butan-1-amine (C₄H₉N): Molecular weight ≈ 73 g/mol
• Butanoic acid (C₄H₈O₂): Molecular weight ≈ 88 g/mol
• Ethanoic acid (C₂H₄O₂): Molecular weight ≈ 60 g/mol
• Iron(II) sulfide (FeS): Molecular weight ≈ 88 g/mol

From the options provided, Ethanoic acid is the only compound that matches the molecular weight of 60 g/mol.

Based on the analysis of the mass spectrum and the comparison with the provided options, the compound identified is B. Butanoic acid.