Science & Nature · 1
What element has the atomic number 1?
Answer
Hydrogen
Hydrogen has atomic number 1, indicating it has exactly one proton in its nucleus, making it the lightest and simplest element. Hydrogen exists primarily in three forms: protium (one neutron), deuterium (one neutron), and tritium (two neutrons). As the most abundant element in the universe by mass, hydrogen is the primary component of stars and comprises about 75% of the universe's normal matter. Hydrogen is essential for life, forming water, organic molecules, and countless chemical compounds.
💡 Did you know?
Hydrogen comprises about 75% of all atoms in the universe and is the fuel that powers the Sun through nuclear fusion.
Other options people guess
- Helium
- Lithium
- Carbon
Topics
- chemistry
- elements
- periodic-table
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