Which of the following statements correctly describes the peaks displayed in a mass spectrum?

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11ecba2d_12b6_14dd_a3bf_65a1d71172c3_MD0008_00 Mass spectrometry is a technique that measures the molecular weight of a molecule. Molecules in a sample are injected into a mass spectrometer, where they are bombarded with a beam of electrons. This beam removes electrons from the molecule and forms a positively charged ion known as the molecular ion. The molecular ion can also fragment during bombardment to form smaller ions. An electric field accelerates the ions toward a magnet, which deflects them according to mass. The strength of the magnetic field is gradually changed during the experiment, and each field strength causes ions of a specific mass to reach the detector while all others are deflected into the walls of the tube. The ions are detected, and a mass spectrum is generated. The y-axis of the mass spectrum represents the ion mass abundance, and the x-axis represents the mass-to-charge ratio (m/z). The mass spectrum can be used to identify the mass of a molecule's fragments by taking the m/z difference between peaks. Samples analyzed by mass spectrometry are ionized and fragmented before detection. Therefore, the peaks observed in the mass spectrum represent ionized fragments of the sample. (Choice A) The peak that corresponds to the highest m/z ratio is typically the molecular ion. This peak may, or may not, be the tallest peak. (Choice B) A sample analyzed by mass spectrometry is ionized when injected, and only ions are detected. Therefore, the peaks represent charged species rather than uncharged molecules. (Choice C) Because the y-axis of a mass spectrum reflects abundance and the x-axis reflects molecular weight, the tallest peak represents the most abundant fragment. Therefore, peak height is not dependent on molecular weight but rather on abundance. Educational objective: Mass spectrometry is a technique that measures the molecular weight of a molecule. Molecules in a sample are bombarded with a beam of electrons, producing positively charged ions and fragments of the molecule. The ionized fragments are detected and a mass spectrum is generated, with the y-axis representing ion abundance and the x-axis representing the mass-to-charge ratio (m/z).

Which of the Following Statements Correctly Describes the Peaks Displayed