---
title: "A student uses spectroscopy to analyze a sample of gaseous water, \\(\\text{H}_2\\text{O(g)}\\). The student observes that the sample absorbs photons in both the infrared (\\(\\text{IR}\\)) region and the microwave region of the electromagnetic spectrum. Which of the following statements correctly compares the energy of the absorbed photons and provides the best justification based on molecular transitions?"
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url: "https://nerd-notes.com/ubq/121377/"
date_modified: "2026-08-23T05:01:58+00:00"
---

# A student uses spectroscopy to analyze a sample of gaseous water, \(\text{H}_2\text{O(g)}\). The student observes that the sample absorbs photons in both the infrared (\(\text{IR}\)) region and the microwave region of the electromagnetic spectrum. Which of the following statements correctly compares the energy of the absorbed photons and provides the best justification based on molecular transitions?

A student uses spectroscopy to analyze a sample of gaseous water, \(\text{H}_2\text{O(g)}\). The student observes that the sample absorbs photons in both the infrared (\(\text{IR}\)) region and the microwave region of the electromagnetic spectrum. Which of the following statements correctly compares the energy of the absorbed photons and provides the best justification based on molecular transitions?

- **A.** Microwave photons have greater energy than \(\text{IR}\) photons because microwave radiation causes transitions between molecular vibrational states, which require larger quanta of energy than rotational transitions.
- **B.** Microwave photons have greater energy than \(\text{IR}\) photons because microwave radiation causes transitions between electronic energy levels, whereas \(\text{IR}\) radiation causes transitions between rotational energy levels.
- **C.** Infrared photons have greater energy than microwave photons because transitions between molecular vibrational states require more energy than transitions between molecular rotational states.
- **D.** Infrared photons have greater energy than microwave photons because \(\text{IR}\) radiation causes transitions between electronic energy levels, whereas microwave radiation causes transitions between vibrational energy levels.

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