Nuclear Chemistry is Weird
Here’s how to make sense of the strangeness of the atomic nucleus
--
There’s a reason I initially felt, shall we say, “uncomfortable” writing about nuclear chemistry, but it wasn’t until I talked to my friend (who has a PhD in nuclear chemistry) in preparation for writing this article that I figured out why. There’s something about nuclear chemistry and nuclear physics that just clashes with classic chemistry ways of thinking, or chemical intuition, as it’s called. It just feels off. We’ll get to what that specifically is later, but there are other fascinating aspects of nuclear chemistry that I want to discuss first. So yeah, today we’re getting into nuclear chemistry because it’s weird — don’t worry, I’ll explain.
Chances are, you’ve heard of nuclear power plants (e.g., Chernobyl) and weapons (e.g., Hiroshima and Nagasaki) — these things are cross-generational. It doesn’t matter if you’re a boomer or a millennial, an X-er, a Y-er, or a Z-er, at some point in your life, the word “nuclear” has popped up on your newsfeed. Consequently, I know you’ve had random follow-up questions: what’s all this about uranium enrichment? Why does it matter that Iran achieved 20% enriched uranium? What is uranium and why do people call it “U-235” and “U-238”? These questions are essentially my starting point today, and from there, we’ll dive into more (or perhaps less) obvious, yet still fascinating questions about nuclear chemistry.
(Hat tip to reader Tim, who was courageous enough to ask these questions and suggest this topic. You, too, can make suggestions — put ’em in the comments!)
Isotopes and “U-238” — the language of nuclear science
Simply put, isotopes are versions of atoms. Much like iOS is on 15.4.1, where it’s still mostly the same save for a few tweaks under the hood, isotopes are versions of an atom with one small tweak: the number of neutrons. The atom’s identity does not change when a neutron is added or removed, which is analogous to how an atom’s identity doesn’t change when an electron is added or removed. Changing the number of neutrons gives you different isotopes; changing the number of electrons gives you different ions.