What causes radioactive decay?
The halflife is the amount of time it takes for half of the atoms in a sample to decay. The halflife for a given isotope is always the same ; it doesn’t depend on how many atoms you have or on how long they’ve been sitting around. There are several ways in which radioactive atoms can decay. Here’s one example: suppose an atom has too many neutrons to be stable.That’s the case with tritium, 3H1. Does it just kick out one of the neutrons? No, it can’t do that; the neutrons are stuck too firmly where they are. The neutron turns into a proton! 3H1 becomes 3He2. Right. An unstable isotope of hydrogen has converted itself into a stable isotope of helium. You’ll notice that 3H1 and 3He2 have the same mass number, which is good, because mass has to be conserved. There is a problem, though. Electric charge also has to be conserved. Hydrogen has only one proton, and helium has two, so you’d end up with twice as much positive charge as you started with. How do you get around that? When 3H metamor
