102
No
Nobelium
259
Nobelium
ACTINIDE
Bohr Model: Electrons arranged in energy shells around the nucleus.
Nobelium is a synthetic chemical element with symbol No and atomic number 102. It is named in honor of Alfred Nobel, the inventor of dynamite and benefactor of science. A radioactive metal, it is the tenth transuranic element and is the penultimate member of the actinide series.
Quick Facts
Atomic Number 102
Period 7
Group 16
Phase Solid
Appearance Unknown
About Actinides
Actinides are the 15 metallic elements with atomic numbers 89–103. All actinides are radioactive.
History
Discovered By Joint Institute for Nuclear Research
Named By Unknown
Physical Properties
Atomic Mass 259
Density N/A g/L
Molar Heat N/A J/(mol·K)
Phase Transition (Melting & Boiling Points)
Nobelium melts at 1100 K. The boiling point is currently unknown.
Atomic Properties
Electron Config [Rn] 5f14 7s2
Electronegativity 1.3
Electron Affinity -223.22 kJ/mol
Ionization Energy 642 kJ/mol
Orbital Filling Diagram
This diagram visualizes electron configuration according to the Aufbau principle and Hund's rule.
Boxes represent orbitals (s, p, d, f), while arrows indicate electrons with spin up or down.
Electrons fill lower energy levels first and occupy orbitals singly before pairing.
Photograph
External Resources
Study Guide
Atomic Number
The number of protons in the nucleus, which defines the element.
Atomic Mass
The average mass of an atom, including protons and neutrons.
Electronegativity
A measure of how strongly an atom attracts electrons in a bond.
Ionization Energy
The energy required to remove an electron from an atom.
Electron Config
The arrangement of electrons in the atom's energy shells.