---
title: "A student investigates electron shielding and the shell model of the atom by comparing the relative populations of inner-shell and outer-shell electrons for main-group elements. Based on the ground-state electron configuration of a neutral bromine atom ( \\(\\text{Br}\\), \\(Z = 35\\)), what is the ratio of the number of core electrons to the number of valence electrons?"
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url: "https://nerd-notes.com/ubq/123456/"
date_modified: "2026-09-28T11:59:48+00:00"
---

# A student investigates electron shielding and the shell model of the atom by comparing the relative populations of inner-shell and outer-shell electrons for main-group elements. Based on the ground-state electron configuration of a neutral bromine atom (
\(\text{Br}\), \(Z = 35\)), what is the ratio of the number of core electrons to the number of valence electrons?

A student investigates electron shielding and the shell model of the atom by comparing the relative populations of inner-shell and outer-shell electrons for main-group elements. Based on the ground-state electron configuration of a neutral bromine atom (
\(\text{Br}\), \(Z = 35\)), what is the ratio of the number of core electrons to the number of valence electrons?

- **A.** \(0.25\)
- **B.** \(2.6\)
- **C.** \(4.0\)
- **D.** \(5.0\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123456/*