---
title: "A student compares the photoelectron spectra of gaseous phosphorus and sulfur atoms. The displayed portion of each spectrum contains the peak produced by ejecting a \\(3s\\) electron, and the peak intensities have been normalized.  Which statement best interprets the relative positions of the peaks?"
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url: "https://nerd-notes.com/ubq/119462/"
date_modified: "2026-08-19T12:40:33+00:00"
---

# A student compares the photoelectron spectra of gaseous phosphorus and sulfur atoms. The displayed portion of each spectrum contains the peak produced by ejecting a \(3s\) electron, and the peak intensities have been normalized.

Which statement best interprets the relative positions of the peaks?

A student compares the photoelectron spectra of gaseous phosphorus and sulfur atoms. The displayed portion of each spectrum contains the peak produced by ejecting a \(3s\) electron, and the peak intensities have been normalized.

Which statement best interprets the relative positions of the peaks?

![Create a grayscale overlay plot of a restricted photoelectron-spectrum region. Draw one horizontal axis labeled “Binding energy (eV)” increasing from left to right, with tick labels 16, 19, 23, and 25. Draw one vertical axis labeled “Relative intensity” with a baseline at zero and no numerical tick labels. Include no gridlines. Draw a solid, narrow, symmetric peak centered exactly above 19 and a dashed, narrow, symmetric peak centered exactly above 23. Both peaks start and return to the same baseline, have equal widths, and reach equal maximum heights. In an open legend box at the upper left, map the solid line to \(\text{P}\ 3s\) and the dashed line to \(\text{S}\ 3s\). No other peaks, labels, text, or annotations appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1787143233-t33Sqb.jpg)

- **A.** The \(3s\) electrons in \(\text{S}\) experience a greater effective nuclear charge because \(\text{S}\) has more neutrons, which increase the attraction between the nucleus and the electrons.
- **B.** The \(3s\) electrons in \(\text{S}\) experience a greater effective nuclear charge because \(\text{S}\) has one more proton, while its additional same-shell electron provides only partial additional shielding.
- **C.** The \(3s\) electrons in \(\text{P}\) experience a greater effective nuclear charge because the lower binding-energy peak indicates that more energy is required to remove an electron.
- **D.** The \(3s\) electrons in \(\text{P}\) experience a greater effective nuclear charge because the additional \(3p\) electron in \(\text{S}\) completely shields the charge of its additional proton.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119462/*