Atom Calculator
Calculate atomic properties including protons, neutrons, electrons, and electron configuration for any element.
Enter Element Data
Positive for cations, negative for anions, 0 for neutral
Results
Enter element data to calculate atomic properties
Atomic Structure
Subatomic Particles
- • Protons: Positive charge, in nucleus
- • Neutrons: No charge, in nucleus
- • Electrons: Negative charge, in orbitals
- • Atomic Number: Number of protons
- • Mass Number: Protons + neutrons
Key Relationships
- • Atomic Number = Protons = Electrons (neutral)
- • Mass Number = Protons + Neutrons
- • Neutrons = Mass Number - Atomic Number
- • Ion Electrons = Protons - Charge
- • Atomic Mass ≈ Mass Number (amu)
Periodic Table Information
Periods
- • Period 1: H, He
- • Period 2: Li to Ne
- • Period 3: Na to Ar
- • Period 4: K to Kr
- • Period 5: Rb to Xe
Groups
- • Group 1: Alkali metals
- • Group 2: Alkaline earth metals
- • Group 17: Halogens
- • Group 18: Noble gases
- • Groups 3-12: Transition metals
Electron Shells
- • K shell: 2 electrons
- • L shell: 8 electrons
- • M shell: 18 electrons
- • N shell: 32 electrons
- • Valence electrons: Outermost shell