---
title: "A sample of copper extracted from a newly discovered meteorite is analyzed using mass spectrometry. The isotopic masses and their relative percent abundances in the extraterrestrial sample are shown in the table below. (For reference, the average atomic mass of terrestrial copper is \\(63.55\\text{ amu}\\).)  | Isotope | Isotopic mass (\\(\\text{amu}\\)) | Relative abundance |  | :— | :— | :— | | \\(^{63}\\text{Cu}\\) | \\(63.00\\) | \\(20.0\\%\\) | | \\(^{65}\\text{Cu}\\) | \\(65.00\\) | \\(80.0\\%\\) |  Based on the data, what is the average atomic mass of copper in this extraterrestrial sample?"
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url: "https://nerd-notes.com/ubq/123476/"
date_modified: "2026-09-28T11:59:52+00:00"
---

# A sample of copper extracted from a newly discovered meteorite is analyzed using mass spectrometry. The isotopic masses and their relative percent abundances in the extraterrestrial sample are shown in the table below. (For reference, the average atomic mass of terrestrial copper is \(63.55\text{ amu}\).)

| Isotope | Isotopic mass (\(\text{amu}\)) | Relative abundance | 
| :— | :— | :— |
| \(^{63}\text{Cu}\) | \(63.00\) | \(20.0\%\) |
| \(^{65}\text{Cu}\) | \(65.00\) | \(80.0\%\) |

Based on the data, what is the average atomic mass of copper in this extraterrestrial sample?

A sample of copper extracted from a newly discovered meteorite is analyzed using mass spectrometry. The isotopic masses and their relative percent abundances in the extraterrestrial sample are shown in the table below. (For reference, the average atomic mass of terrestrial copper is \(63.55\text{ amu}\).)

| Isotope | Isotopic mass (\(\text{amu}\)) | Relative abundance | 
| :--- | :--- | :--- |
| \(^{63}\text{Cu}\) | \(63.00\) | \(20.0\%\) |
| \(^{65}\text{Cu}\) | \(65.00\) | \(80.0\%\) |

Based on the data, what is the average atomic mass of copper in this extraterrestrial sample?

- **A.** \(63.40\text{ amu}\)
- **B.** \(63.55\text{ amu}\)
- **C.** \(64.00\text{ amu}\)
- **D.** \(64.60\text{ amu}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123476/*