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
Know your science & nature trivia?
Play a free Science & Nature quiz and see how many you get right — no signup needed to start.
More Science & Nature facts
Science & Nature
What is the only letter that does not appear on the periodic table of elements?
Out of 118 elements, not a single one has a 'J' in its symbol—this quirk has persisted for over a century.
Science & Nature
What is the second most abundant element in the human body by mass?
Carbon forms the backbone of every protein, carbohydrate, lipid, and nucleotide—making it essential to all known life.
Science & Nature
Which element has the highest melting point of all metals?
Tungsten is so heat-resistant it's used in the nose cones of spacecraft re-entering Earth's atmosphere.
Science & Nature
What is the name of the response where your pupils dilate in low light?
Your pupils can change size within milliseconds, allowing you to maintain clear vision across a billion-fold range of light intensities.
Science & Nature
What is the name of the tough, flexible connective tissue that covers the ends of bones?
Your ears and nose are made of flexible hyaline cartilage that can bend and return to shape, unlike rigid bone.
Science & Nature
What is the collective term for organisms that produce their own food through photosynthesis?
Producers form the foundation of nearly all ecosystems, supporting all herbivores, carnivores, and every other organism above them in food chains.