---
title: "A sample of pure boron is analyzed using mass spectrometry. The resulting mass spectrum is shown below. Based on the mass spectrum, which of the following is the average atomic mass of boron in the sample?"
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url: "https://nerd-notes.com/ubq/119934/"
date_modified: "2026-08-21T08:18:30+00:00"
---

# A sample of pure boron is analyzed using mass spectrometry. The resulting mass spectrum is shown below. Based on the mass spectrum, which of the following is the average atomic mass of boron in the sample?

A sample of pure boron is analyzed using mass spectrometry. The resulting mass spectrum is shown below. Based on the mass spectrum, which of the following is the average atomic mass of boron in the sample?

![A mass spectrum displayed on a Cartesian grid with grayscale rendering. The horizontal axis is labeled Mass-to-Charge Ratio (\(m/z\)) with major tick marks at \(9\), \(10\), \(11\), and \(12\). The vertical axis is labeled Relative Intensity with major tick marks and horizontal dashed gridlines at \(0\), \(25\), \(50\), \(75\), and \(100\). Two vertical solid black bars appear on the graph. The first bar is centered at \(m/z = 10\) and extends vertically from \(0\) to exactly \(25\). The second bar is centered at \(m/z = 11\) and extends vertically from \(0\) to exactly \(100\). No other peaks, lines, labels, or annotations appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1787300309-ar1CpB.jpg)

- **A.** \(10.20\text{ amu}\)
- **B.** \(10.80\text{ amu}\)
- **C.** \(11.00\text{ amu}\)
- **D.** \(11.25\text{ amu}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119934/*