Here is the equation for the alpha decay of radon-219 into polonium. Beta decay involves the conversion of a down quark to an up quark. This changes a neutron into a proton plus an electron.
That happens when the element emits radiation (such as alpha particles) and decays into a lighter element. Pu-238 has a half-life of 87.7 years, making it a much longer-lasting source of energy than ...
In the UK, two Russian ex-secret service agents were targeted: Alexander Litvinenko fatally with radioactive polonium-210 in 2006, and Sergei Skripal with the toxic nerve agent Novichok in 2018.
In 2006, Alexander Litvinenko - an ex-Russian intelligence officer who became a Kremlin critic and fled to the UK - died after his tea was poisoned by radioactive polonium-210. More recently ...