Atomic Number
5
Element 5
Boron (B)
Boron is a chemical element with symbol B and atomic number 5. It is a low-abundance element in the Solar system and in the Earth's crust.
Atomic Mass
10.81 u
Category
Metalloid
Period
2
Group
Group 13: boron group
Phase
solid
Density
2.34 g/cm3
Electron Shells
2, 3
Atomic Structure
Protons: 5. Electrons: 5. Neutrons: Varies by isotope.
Electron configuration: 1s² 2s² 2p¹
Why Boron Matters
Boron helps connect atomic number 5, metalloid behavior, period 2 trends, and electron shell structure. Its solid phase, atomic mass of 10.81 u, and electron configuration 1s² 2s² 2p¹ make it useful for comparing bonding patterns across the periodic table.
Discovery and Occurrence
Boron was discovered 1808 by Joseph Louis Gay-Lussac, Louis Jacques Thénard. Boron is a chemical element with symbol B and atomic number 5. It is a low-abundance element in the Solar system and in the Earth's crust.
Safety and Handling Context
Boron 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 Boron?
- Boron has atomic number 5, which means a neutral atom has 5 protons and 5 electrons.
- What is the chemical symbol for Boron?
- The chemical symbol for Boron is B.
- What category is Boron in?
- Boron is classified as a metalloid and sits in period 2 of the periodic table.
Explore Boron in 3D
Use the interactive table above to rotate atomic models, compare periodic trends, and move from Boron to neighboring elements without losing your place.