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H

Hydrogen

Atomic number: 1Mass: 1.008 uCategory: Nonmetal

About Hydrogen

Hydrogen is the lightest and most abundant element in the universe. It makes up about 75% of all normal matter by mass. On Earth, it exists mostly in compounds like water (H₂O).

Properties

Period
1
Group
1
Block
S
Category
Nonmetal
Electronegativity
2.20 (Pauling)
Ionization Energy
1312 kJ/mol
Melting Point
14 K (-259°C)
Boiling Point
20 K (-253°C)
Density
0.090 g/L
Oxidation States
-1, +1

Electron Configuration

1s¹
1s¹
Shell 1:1e⁻

Real-World Uses

Rocket fuel
Fuel cells
Fertilizer production
Oil refining
Welding

Fun Fact

The Sun burns 600 million tonnes of hydrogen every second through nuclear fusion!