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title: "Naturally occurring bromine consists of two stable isotopes, \\(^{79}\\text{Br}\\) and \\(^{81}\\text{Br}\\), with approximate percent abundances of \\(50.0\\%\\) and \\(50.0\\%\\), respectively. A sample of pure diatomic bromine gas, \\(\\text{Br}_2\\text{(g)}\\), is analyzed using mass spectrometry under ionization conditions that produce the intact molecular ion, \\(\\text{Br}_2^+\\). Which of the following mass spectra best represents the molecular ion region (\\(m/z = 156\\) to \\(164\\)) for \\(\\text{Br}_2^+\\)?"
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url: "https://nerd-notes.com/ubq/120204/"
date_modified: "2026-08-21T16:03:05+00:00"
---

# Naturally occurring bromine consists of two stable isotopes, \(^{79}\text{Br}\) and \(^{81}\text{Br}\), with approximate percent abundances of \(50.0\%\) and \(50.0\%\), respectively. A sample of pure diatomic bromine gas, \(\text{Br}_2\text{(g)}\), is analyzed using mass spectrometry under ionization conditions that produce the intact molecular ion, \(\text{Br}_2^+\). Which of the following mass spectra best represents the molecular ion region (\(m/z = 156\) to \(164\)) for \(\text{Br}_2^+\)?

Naturally occurring bromine consists of two stable isotopes, \(^{79}\text{Br}\) and \(^{81}\text{Br}\), with approximate percent abundances of \(50.0\%\) and \(50.0\%\), respectively. A sample of pure diatomic bromine gas, \(\text{Br}_2\text{(g)}\), is analyzed using mass spectrometry under ionization conditions that produce the intact molecular ion, \(\text{Br}_2^+\). Which of the following mass spectra best represents the molecular ion region (\(m/z = 156\) to \(164\)) for \(\text{Br}_2^+\)?

- **A.** Spectrum A
- **B.** Spectrum B
- **C.** Spectrum C
- **D.** Spectrum D

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120204/*