Atomic Number
56
Element 56
Barium (Ba)
Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal.
Atomic Mass
137.33 u
Category
Alkaline Earth Metal
Period
6
Group
Group 2: alkaline earth metals
Phase
solid
Density
3.51 g/cm3
Electron Shells
2, 8, 18, 18, 8, 2
Atomic Structure
Protons: 56. Electrons: 56. Neutrons: Varies by isotope.
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s²
Why Barium Matters
Barium helps connect atomic number 56, alkaline earth metal behavior, period 6 trends, and electron shell structure. Its solid phase, atomic mass of 137.33 u, and electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² make it useful for comparing bonding patterns across the periodic table.
Discovery and Occurrence
Barium was discovered 1808 by Humphry Davy. Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal.
Safety and Handling Context
Barium is presented here for learning and comparison. Pure elements and laboratory compounds can have hazards that depend on dose, form, and setting.
Related Elements
Frequently Asked Questions
- What is the atomic number of Barium?
- Barium has atomic number 56, which means a neutral atom has 56 protons and 56 electrons.
- What is the chemical symbol for Barium?
- The chemical symbol for Barium is Ba.
- What category is Barium in?
- Barium is classified as a alkaline earth metal and sits in period 6 of the periodic table.
Explore Barium in 3D
Use the interactive table above to rotate atomic models, compare periodic trends, and move from Barium to neighboring elements without losing your place.