Decay Simulator: Krypton-99
General data
| Element name | Krypton |
|---|---|
| Chemical symbol | Kr |
| Atomic number Z | 36 |
| Isotope name (symbol) | Krypton-99 (Kr-99) |
| Neutron number N | 63 |
| Mass number A=Z+N | 99 |
Interactive radioactive decay simulation of Krypton-99: atom-by-atom decay, full decay chain, charts of nuclei count and activity.
| Half-life | 10 ms |
|---|
Radioactive decay series
- Krypton-99 10 ms
- Rubidium-99 54 ms · 89.0%
- Strontium-99 269 ms · 71.4%
- Yttrium-99 1.483 s · 71.3%
- Zirconium-99 2.1 s · 70.0%
- Niobium-99 15.0 s · 70.0%
- Molybdenum-99 65.936 h · 70.0%
- Technetium-99 2.111×10⁵ a · 70.0%
- Ruthenium-99 stable · 70.0%
- Rubidium-98 115 ms · 11.0%
- Strontium-98 653 ms · 27.0%
- Yttrium-98 548 ms · 27.1%
- Zirconium-98 30.7 s · 28.2%
- Niobium-98 2.86 s · 28.2%
- Molybdenum-98 stable · 28.2%
- Strontium-97 431 ms · 1.6%
- Yttrium-97 3.75 s · 1.6%
- Zirconium-97 16.749 h · 1.7%
- Niobium-97 72.1 min · 1.7%
- Molybdenum-97 stable · 1.7%
Rare branches (below 0.01%)
Rare branches are transformations that occur in fewer than 0.01% of decays, e.g. double beta decay or cluster emission. The nuclides they produce are practically absent from a sample, so they are hidden by default to keep the main path clear. In this series: branches - 3, nuclides - 4.
- Strontium-96 1.065 s · 0.0059%
- Yttrium-96 5.35 s · 0.0064%
- Zirconium-96 2.29×10¹⁹ a · 0.0073%
- Molybdenum-96 stable · 0.0073%
How to read the simulation
Grid: each pixel is one atom of the starting isotope. When an atom decays, the pixel takes the colour of the decay product - in decay series mode the product can decay further. The moment each atom decays is random, but the probability follows from the half-life, so after one T½ about half of the atoms remain, after two - about a quarter.
Chart N(t): what percentage of the sample atoms each nuclide makes up at a given moment. The line of the starting isotope falls (by half after each T½), the lines of stable products rise, and those of short-lived ones first rise, then fall.
Chart A(t): activity, i.e. the number of decays per second (becquerel, Bq). It depends on the number of atoms and on how fast they decay: for the same number of atoms, the shorter the T½, the higher the activity.
Simulation time runs faster (or slower) than real time - the time scale slider sets the multiplier. This way you can watch the decay of isotopes that live from fractions of a second to billions of years.
Well-known isotopes
- H-3 - Tritium - glowing watch hands, nuclear fusion fuel.
- C-14 - Radiocarbon dating.
- K-40 - Natural radioactivity - in bananas and in our bodies.
- Co-60 - Radiotherapy and radiation sterilization.
- I-131 - Thyroid treatment; Chernobyl fallout.
- Cs-137 - Long-lasting contamination after Chernobyl and Fukushima.
- Rn-222 - Radon in basements and mines.
- Ra-226 - The longest-lived isotope of radium - the element discovered by Marie and Pierre Curie in 1898.
- U-235 - Nuclear power plant fuel; start of the actinium series.
- U-238 - Age of the Earth; start of the uranium series.
- Pu-238 - Power source for space probes (Voyager, Curiosity rover).
- Am-241 - Ionization smoke detectors.
Data sources
- NNDC Wallet Cards 2023 - Data as of 15 October 2024 - licence: Public domain