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Subatomic Atom Builder

Rutherford-Bohr & Nuclear Dynamics

Principles & Guide

Subatomic Particles: Protons (p⁺) determine atomic number $Z$ and element identity; Neutrons (n⁰) stabilize the nucleus via the residual strong force; Electrons (e⁻) orbit in quantized shells $n=1..7$.

Nuclear Stability: Stable light nuclei require $N/Z \approx 1.0$, increasing to $N/Z \approx 1.54$ for heavy elements. Nuclei outside the Valley of Stability decay via $\beta^-$, $\beta^+$/EC, or $\alpha$ emission.

Binding Energy (SEMF): Calculated via the Bethe-Weizsäcker Liquid Drop formula ($E = \Delta m \cdot c^2$). $B/A$ peaks at $^{56}\text{Fe}$ (~8.79 MeV/nucleon).

Subatomic Particles Range: Z 1–118
Protons (Z) +1e each
Neutrons (N) 0e (Neutral)
Electrons (e⁻) -1e each
Quantum Orbital Motion
Show Orbital Radii Labels
Nuclear Stability & Forces
Stable Nuclide N/Z = 1.00
Binding Energy / Nucleon (B/A): 7.07 MeV
0 MeV Peak 8.79 MeV (⁵⁶Fe)
Mass Defect (Δm)
0.0304 u
Total Binding (B)
28.30 MeV
Strong Nuclear Cohesion Coulomb Repulsion
4 2
He 0
Helium
Neutral Atom
Shells (n=1..7):
K: 2
Proton ($m_p = 1.00728\text{ u}$) Neutron ($m_n = 1.00866\text{ u}$) Electron ($m_e = 0.00055\text{ u}$)
Ground State • Liquid Drop SEMF Mode