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Element story

Rhodium

Atomic number 45 means that every Rhodium nucleus contains 45 protons. That proton count is the element's identity: change it and you no longer have Rhodium.

Start with the nucleus

Atomic number 45 means that every Rhodium nucleus contains 45 protons. That proton count is the element's identity: change it and you no longer have Rhodium.

Rhodium (Rh) is chemical element 45. It belongs to the transition 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 catalysts, reflectors and jewellery.

See the atom

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

What this number means

Atomic number 45 means that every Rhodium nucleus contains 45 protons. That proton count is the element's identity: change it and you no longer have Rhodium.

Keep exploring

→ Rhodium · Atomic structure · Periodic trends

45RhRhodium
Rhodium · Rh · Z = 45

Rhodium (Rh) is chemical element 45. It belongs to the transition 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

Rhodium (Rh) is chemical element 45. It belongs to the transition 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 catalysts, reflectors and jewellery.

What its position in the table tells us

Rhodium sits in period 5, group 9 and the D block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.