Rutherfordium
Atomic number 104 means that every Rutherfordium nucleus contains 104 protons. That proton count is the element's identity: change it and you no longer have Rutherfordium.
Start with the nucleus
Atomic number 104 means that every Rutherfordium nucleus contains 104 protons. That proton count is the element's identity: change it and you no longer have Rutherfordium.
Rutherfordium (Rf) is chemical element 104. It belongs to the transition metals, and its reference state at room temperature is not firmly established. 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 104 means that every Rutherfordium nucleus contains 104 protons. That proton count is the element's identity: change it and you no longer have Rutherfordium.