Hydrogen is the first element on the periodic table with atomic number 1. It's also the lightest and most abundant element in the universe, making up about 75% of its elemental mass.
Hydrogen is like the basic building block in a LEGO set. It's simple and small on its own, but it can combine with other blocks (or elements) to create complex structures.
Proton: A subatomic particle found in the nucleus of every atom. The number of protons in an atom determines what element it is.
Electron: A subatomic particle that carries a negative electric charge. It orbits around the nucleus of an atom.
Atomic Number: This is defined as the number of protons found in the nucleus of an atom, which also defines its chemical properties.
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