Mendeleev
Periodic table · chemistry · physics
Element story

Hydrogen

Atomic number 1 means that every Hydrogen nucleus contains 1 protons. That proton count is the element's identity: change it and you no longer have Hydrogen.

Start with the nucleus

Atomic number 1 means that every Hydrogen nucleus contains 1 protons. That proton count is the element's identity: change it and you no longer have Hydrogen.

Hydrogen (H) is chemical element 1. It belongs to the nonmetals, and its reference state at room temperature is a gas. Those basic facts are a useful starting point for its chemistry and applications.

In practice, it turns up most often in water and the chemistry of life, fertiliser production and oil refining.

See the atom

Conceptual visual: electron shells are a learning aid, not a literal picture of quantum orbitals.

What this number means

Atomic number 1 means that every Hydrogen nucleus contains 1 protons. That proton count is the element's identity: change it and you no longer have Hydrogen.

Keep exploring

→ Hydrogen · Atomic structure · Periodic trends

1HHydrogen
Hydrogen · H · Z = 1

Hydrogen (H) is chemical element 1. It belongs to the nonmetals, and its reference state at room temperature is a gas. Those basic facts are a useful starting point for its chemistry and applications.

Understanding the element

Hydrogen (H) is chemical element 1. It belongs to the nonmetals, and its reference state at room temperature is a gas. Those basic facts are a useful starting point for its chemistry and applications.

Where do we encounter it?

In practice, it turns up most often in water and the chemistry of life, fertiliser production and oil refining.

What its position in the table tells us

Hydrogen sits in period 1, group 1 and the S block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.