Some isotopes are stable, while others are radioactive and decay over time, emitting radiation. Carbon-14 is a radioactive isotope of carbon, meaning that it undergoes beta decay, releasing electrons.

The half-life of radioactive carbon-14 is 5,730 years. If a sample of a tree (for example) contains 64 grams (g) of radioactive carbon after 5,730 years it will contain 32 g, after another 5,730 ...

The decay, seen in xenon-124 atoms, happens so sparingly that it would take 18 sextillion years (18 followed by 21 zeros) for a sample of xenon-124 to shrink by half, making the decay extremely ...

That's because internal heating from the radioactive decay of the heavy elements thorium and uranium drives plate tectonics and may be necessary for the planet to generate a magnetic field. Earth ...

Radioactive decay is the strange and almost mystical ability for one element to naturally and spontaneously transmute into another. In the process, those elements tend to emit deadly forms of ...

Then, contending with radioactive decay was another challenge. The Berkeley Lab team conducted their experiments with einsteinium-254, one of the more stable isotopes of the element.

Joel A. Bryan, Using Radioactive Decay to Investigate Exponential Functions, The Mathematics Teacher, Vol. 106, No. 1 (August 2012), pp. 52-58 ...

Element 99 — mysterious and exceptionally radioactive — sits inconspicuously in the bottom row of the periodic table. Named for legendary physicist Albert Einstein, einsteinium has been one of ...

The blue spheres are radioactive, and decay at the same rate I used in the example above. Click play to see what that might look like. Again, I made radioactive spheres disappear when they decayed.