Atomic Number
35
Element 35
Bromine (Br)
Bromine is a chemical element with symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly coloured gas.
Atomic Mass
79.904 u
Category
Halogen
Period
4
Group
Group 17: halogens
Phase
liquid
Density
3.1028 g/cm3
Electron Shells
2, 8, 18, 7
Atomic Structure
Protons: 35. Electrons: 35. Neutrons: Varies by isotope.
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁵
Why Bromine Matters
Bromine helps connect atomic number 35, halogen behavior, period 4 trends, and electron shell structure. Its liquid phase, atomic mass of 79.904 u, and electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁵ make it useful for comparing bonding patterns across the periodic table.
Discovery and Occurrence
Bromine was discovered 1825 by Antoine Jérôme Balard, Carl Jacob Löwig. Bromine is a chemical element with symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly coloured gas.
Safety and Handling Context
Bromine belongs to the halogen family, where many pure elements are reactive and irritating or toxic at high concentrations. Classroom work should use approved compounds and teacher guidance.
Related Elements
Frequently Asked Questions
- What is the atomic number of Bromine?
- Bromine has atomic number 35, which means a neutral atom has 35 protons and 35 electrons.
- What is the chemical symbol for Bromine?
- The chemical symbol for Bromine is Br.
- What category is Bromine in?
- Bromine is classified as a halogen and sits in period 4 of the periodic table.
Explore Bromine in 3D
Use the interactive table above to rotate atomic models, compare periodic trends, and move from Bromine to neighboring elements without losing your place.