Atomic Number
26
Element 26
Iron (Fe)
Iron is a chemical element with symbol Fe and atomic number 26. It is a metal in the first transition series. It is by mass the most common element on Earth, forming much of Earth's outer and inner core.
Atomic Mass
55.845 u
Category
Transition Metal
Period
4
Group
Group 8: iron group
Phase
solid
Density
7.874 g/cm3
Electron Shells
2, 8, 14, 2
Atomic Structure
Protons: 26. Electrons: 26. Neutrons: Varies by isotope.
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶
Why Iron Matters
Iron helps connect atomic number 26, transition metal behavior, period 4 trends, and electron shell structure. Its solid phase, atomic mass of 55.845 u, and electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶ make it useful for comparing bonding patterns across the periodic table.
Discovery and Occurrence
Iron was discovered Unknown. Iron is a chemical element with symbol Fe and atomic number 26. It is a metal in the first transition series. It is by mass the most common element on Earth, forming much of Earth's outer and inner core.
Safety and Handling Context
Iron 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 Iron?
- Iron has atomic number 26, which means a neutral atom has 26 protons and 26 electrons.
- What is the chemical symbol for Iron?
- The chemical symbol for Iron is Fe.
- What category is Iron in?
- Iron is classified as a transition metal and sits in period 4 of the periodic table.
Explore Iron in 3D
Use the interactive table above to rotate atomic models, compare periodic trends, and move from Iron to neighboring elements without losing your place.