I

Iron

IUPAC: Iron

Fe Elements CAS 7439-89-6
Quick Reference
Formula / NotationFe
CAS Number7439-89-6
Molecular Weight55.85
Melting Point1538.0
Boiling Point2861.0
Density7.87
SolubilityInsoluble in water
AppearanceLustrous, silver-grey metal; rusts to reddish-brown
Also Known AsFe, ferrum, iron metal
CategoryElements

What is Iron?

Iron is a lustrous, silver-grey transition metal, atomic number 26. The most used metal in the world - primarily as steel. Fourth most abundant element in Earth crust. Essential for life as core of haemoglobin, myoglobin, and many enzymes. Earth core is primarily iron and nickel.

Formula & Notation

Fe

IUPAC Name: Iron

Other Names / Synonyms: Fe, ferrum, iron metal

Properties & Characteristics

Atomic number: 26. Atomic mass: 55.845 g/mol. Period 4, Group 8. Melting point: 1538 C. Boiling point: 2861 C. Density: 7.87 g/cm3. Electronegativity: 1.83. Oxidation states: 0, +2, +3, +6. Ferromagnetic below 770 C (Curie temp). Four stable isotopes.

Physical Data

PropertyValue
Melting Point1538.0
Boiling Point2861.0
Density7.87
Molecular Weight55.85
SolubilityInsoluble in water
AppearanceLustrous, silver-grey metal; rusts to reddish-brown

Uses & Applications

Steel production (by far largest use). Cast iron for engine blocks, cookware. Iron compounds in medicine (anaemia treatment). Magnets (iron-based permanent magnets). Catalysts (Haber process uses Fe catalyst). Pigments (iron oxides - red, yellow, black).

Safety Information

Iron powder/dust: combustible, fire risk. Iron (II) and (III) compounds: irritants, moderate toxicity by ingestion. Iron overload disease (haemochromatosis). Iron pentacarbonyl (Fe(CO)5): highly toxic liquid. Rust (Fe2O3) not acutely toxic. Welding fumes: irritant and potential carcinogen.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Iron
Formula Fe
CAS Number 7439-89-6
Molecular Weight 55.85
Category Elements
Synonyms Fe, ferrum, iron metal

Frequently Asked Questions

Iron is a lustrous, silver-grey transition metal, atomic number 26. The most used metal in the world - primarily as steel. Fourth most abundant element in Earth crust. Essential for life as core of haemoglobin, myoglobin, and many enzymes. Earth core is primarily iron and nickel.

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