What is the atomic number of hydrogen?

Hydrogen is a chemical element with symbol H and atomic number 1. With a standard atomic weight of1.008, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass. read more

Hydrogen is a chemical element with symbol H and atomic number 1. With a standard atomic weight of 1.008, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass. read more

Atomic Number of Hydrogen = 1 This means that the number of protons in a hydrogen atom, represented by Z , is equal to 1. Furthermore, all isotopes of an element typically have the same number of protons and different number of neutrons. read more

Atomic number 2 is the second most abundant element in the universe, after hydrogen. However, the element is rare on Earth (5.2 ppm by volume in the atmosphere) because nonreactive helium is light enough that it can escape Earth's gravity and be lost to space. read more