Nuclear chemistry requires an understanding of the atomic nucleus, which we've already explored a bit in this guide. Nuclear chemistry also involves explosions, although nuclear explosions are of much larger proportions that anything we see on YouTube. Yikes.
Interestingly, nuclear reactions are not the result of changes in chemical bonding. Instead, nuclear chemistry is rooted in changes in individual atoms—the nucleus of the atom to be exact. Seeing where nuclear chemistry gets its name? Here are a few different types of nuclear reactions that we will explore later in greater detail.
Nuclear fusion refers to when subatomic particles come together, or fuse. The result is a ton of energy, and we mean a ton. Want an example? Take a look at the sun. Well, actually just think about the sun—we want to protect our eyeballs, especially after we go through all the trouble of wearing annoying safety goggles in lab. The energy generated from the sun is an example of nuclear fusion. On the sun, four protons fuse together to make helium atoms and in the process, energy is liberated. Who ever said there isn't such a thing as free energy?
Nuclear fission occurs when atoms with large atomic masses split apart. We are talking about mass numbers of 230 or more; these are the big guys of the periodic table3. However, these reactions are slow, even by chemistry standards. If you had a sample of uranium, it would take 10,000,000,000,000,000 years for half of the sample to undergo nuclear fission3. Chemists use nuclear reactors to induce nuclear fission reactions so that they don't have to wait around so long. Seriously, some science experiments take forever.
The process of unstable atoms breaking down and releasing energy is called radioactive decay. There are a few different types of decay: alpha decay, beta decay, gamma decay, and tooth decay. (One of those isn't quite right.) The other types of decay aren't too good for you, either.
Your skin easily blocks alpha particles, released by alpha decay. However, if you should ingest alpha particles, that's a real problem. Read more about the fatal poisoning of a spy by polonium. A sheet of aluminum can stop beta particles, but they are also potential hazards as beta particles can mutate DNA. Mutated DNA leads to things like Teenage Mutant Ninja Turtles walking around the streets...scary. Gamma rays are the most harmful as they are very high energy, and it takes a block of lead to stop them from penetrating the body. Ever wonder why the dentist puts a lead apron on your body right before taking X-rays of your teeth? (We knew this would come full circle.) The answer is that the apron is there to protect your body from the X-rays, which would otherwise needlessly expose your body to extra gamma radiation.
We promise we will return to the land of nuclear reactions in a later section. We have just scratched the surface. There's still the topic of radioactive dating to explore. No, we don't mean dinner and a movie.