Mendeleev
Periodic table · chemistry · physics
Element story

Francium

Atomic number 87 means that every Francium nucleus contains 87 protons. That proton count is the element's identity: change it and you no longer have Francium.

Start with the nucleus

Atomic number 87 means that every Francium nucleus contains 87 protons. That proton count is the element's identity: change it and you no longer have Francium.

Francium (Fr) is chemical element 87. 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 scientific research.

See the atom

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

What this number means

Atomic number 87 means that every Francium nucleus contains 87 protons. That proton count is the element's identity: change it and you no longer have Francium.

Keep exploring

→ Francium · Atomic structure · Periodic trends

87FrFrancium
Francium · Fr · Z = 87

Francium (Fr) is chemical element 87. 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

Francium (Fr) is chemical element 87. 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 scientific research.

What its position in the table tells us

Francium sits in period 7, group 1 and the S block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.