Decay Simulator: Thorium-210
General data
| Element name | Thorium |
|---|---|
| Chemical symbol | Th |
| Atomic number Z | 90 |
| Isotope name (symbol) | Thorium-210 (Th-210) |
| Neutron number N | 120 |
| Mass number A=Z+N | 210 |
Interactive radioactive decay simulation of Thorium-210: atom-by-atom decay, full decay chain, charts of nuclei count and activity.
| Half-life | 16 ms |
|---|
Radioactive decay series
- Thorium-210 16 ms
- Radium-206 240 ms
- Radon-202 9.75 s
- Polonium-198 1.76 min · 78.0%
- Lead-194 10.7 min · 44.5%
- Thallium-194 33.3 min · 44.5%
- Mercury-194 450 a · 44.5%
- Gold-194 38.06 h · 44.5%
- Platinum-194 stable · 44.5%
- Astatine-202 184 s · 22.0%
- Bismuth-198 10.3 min · 36.2%
- Polonium-202 44.6 min · 19.4%
- Lead-198 2.4 h · 36.6%
- Thallium-198 5.3 h · 36.6%
- Mercury-198 stable · 36.6%
- Bismuth-202 1.71 h · 19.0%
- Lead-202 53000 a · 19.0%
- Thallium-202 12.471 d · 19.0%
- Mercury-202 stable · 19.0%
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 - 1, nuclides - 5.
- Mercury-190 20.0 min · 3.2×10⁻⁶%
- Gold-190 42.8 min · 3.2×10⁻⁶%
- Platinum-190 4.90×10¹¹ a · 3.2×10⁻⁶%
- Osmium-186 2.0×10¹⁵ a · 3.2×10⁻⁶%
- Tungsten-182 stable · 3.2×10⁻⁶%
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