Nuclear Symbol Calculator
Decode or construct nuclear symbols: identify element, mass number A, atomic number Z, and number of neutrons from AZX notation. Find protons, neutrons, and electrons for any nuclide.
☢️ Nuclear Chemistry📐 X: A = Z + N🧪 Chemistry
Atomic number Z (protons)
Mass number A (protons + neutrons)
OR element symbol and A (e.g. U-238)
Please enter valid values.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| Nuclear Symbol Calculator | — | X: A = Z + N | nuclide |
Step-by-Step Examples
Example 1
Uranium-238
Z=92, A=238.
- Element: Uranium (U)
- N = A - Z = 238 - 92 = 146 neutrons
- Notation: 238U or U-238
✓ U-238: 92 protons, 146 neutrons, 92 electrons
Example 2
Carbon-14
Z=6, A=14.
- Element: Carbon (C)
- N = 14 - 6 = 8 neutrons
- C-12 (stable): 6 neutrons; C-14 (radioactive): 8 neutrons
✓ C-14: 6 protons, 8 neutrons, 6 electrons
Example 3
Iron-56
Z=26, A=56.
- Element: Iron (Fe)
- N = 56 - 26 = 30 neutrons
- Fe-56: most stable iron isotope; highest binding energy per nucleon
✓ Fe-56: 26 protons, 30 neutrons, 26 electrons
Real-World Applications
Nuclear Medicine
Tc-99m (Z=43, A=99), I-131 (Z=53, A=131) used in diagnosis and therapy.
Nuclear Reactions
Balancing nuclear equations requires tracking Z and A separately.
Radiometric Dating
C-14 (Z=6, A=14, N=8) used for dating organic materials up to 50,000 years.
Research
Isotope labels (C-13, N-15, D) tracked in biochemical pathways using nuclear symbols.
Common Mistakes to Avoid
⚠️
A = Z + N always
Mass number = protons + neutrons. Neutrons = A - Z. Electrons in neutral atom = Z.
⚠️
Isotopes have same Z, different A
C-12 and C-14: both Z=6, but A=12 vs A=14. Different number of neutrons.
⚠️
Isobars have same A, different Z
C-14 and N-14: both A=14. Different Z, different elements.
Frequently Asked Questions
What is a nuclide? ▾
A specific isotope identified by Z and A. C-12 and C-14 are different nuclides of carbon. About 250 stable nuclides and ~3000 known unstable nuclides.
What are isotones? ▾
Nuclides with same number of neutrons (N) but different Z and A. C-14 and N-15: both N=7. Different elements, same neutron count.
What is nuclear stability? ▾
Stable nuclides have N/Z ratios in the valley of stability. Light elements: N/Z ~ 1. Heavy elements: N/Z ~ 1.5. Outside the valley: radioactive.
What is the magic number? ▾
Nuclei with Z or N = 2, 8, 20, 28, 50, 82, 126 (magic numbers) are especially stable. He-4 (Z=2, N=2): doubly magic and very stable.
What is isomeric transition? ▾
Some nuclides exist in excited nuclear state (metastable, denoted m). Tc-99m: metastable Tc-99. Relaxes by gamma emission to ground state Tc-99.
Related Chemistry Calculators
Formula Explorer connections
Interpretation: This relationship connects isotopic composition, decay, radiation, mass defect or nuclear energy to a measurable quantity. Assumption: Use the correct nuclide, decay constant, branching behavior and time units. Radiation estimates also depend on geometry, shielding and detector response.