Tantalum
Atomic number 73 means that every Tantalum nucleus contains 73 protons. That proton count is the element's identity: change it and you no longer have Tantalum.
Start with the nucleus
Atomic number 73 means that every Tantalum nucleus contains 73 protons. That proton count is the element's identity: change it and you no longer have Tantalum.
Tantalum (Ta) is chemical element 73. 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 capacitors, implants and superalloys.
See the atom
Conceptual visual: electron shells are a learning aid, not a literal picture of quantum orbitals.
What this number means
Atomic number 73 means that every Tantalum nucleus contains 73 protons. That proton count is the element's identity: change it and you no longer have Tantalum.