Here, Anna Nalick questons how a "simple chemical reaction" can be the reason, or catalyst, for love. She first wrote the song in chemistry class in high school before recording it for her debut album Wreck of the Day a few years later. Nalick recalled to Billboard
"At the time I didn't really think about it. I guess I found metaphors in everything. So, it wasn't a surprise that I heard a new word that meant something that could also mean something in terms of love. Thinking back on having written my first album in class in high school: things like that make me laugh all the time."