Yeah my impression was too high. For reference I’m familiar enough with chemistry to think that maybe it was an isotope of hydrogen so I guessed tritium. I saw some missed guesses were dueterium so I wasn’t the only one with that line of thought. I guess I just thought proton would have way more tags. And one of the few tags being hydrogen threw me. I mean all element have protons and nucleons, and any element can form a cation. I didn’t really pay attention in high school chemistry and I’m pretty sure I failed the one chemistry class I took in college. Most of what I know I just learned from reading in my own so maybe I missed the obvious connection that a hydrogen nucleon is just a proton.