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Element story

Potassium

Atomic number 19 means that every Potassium nucleus contains 19 protons. That proton count is the element's identity: change it and you no longer have Potassium.

Start with the nucleus

Atomic number 19 means that every Potassium nucleus contains 19 protons. That proton count is the element's identity: change it and you no longer have Potassium.

Potassium (K) is chemical element 19. It belongs to the alkali metals, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

In practice, it turns up most often in fertiliser production, biology and soaps and chemical bases.

See the atom

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

What this number means

Atomic number 19 means that every Potassium nucleus contains 19 protons. That proton count is the element's identity: change it and you no longer have Potassium.

Keep exploring

→ Potassium · Atomic structure · Periodic trends

19KPotassium
Potassium · K · Z = 19

Potassium (K) is chemical element 19. It belongs to the alkali metals, and its reference state at room temperature is a solid. Those basic facts are a useful starting point for its chemistry and applications.

Understanding the element

Potassium (K) is chemical element 19. It belongs to the alkali metals, and its reference state at room temperature is a solid. 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 fertiliser production, biology and soaps and chemical bases.

What its position in the table tells us

Potassium sits in period 4, group 1 and the S block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.