<p>uhhh chem is definitely the more mathematical major. bio is pretty conceptual (at least in the sense that you have to be really good at understanding molecular processes and why they occur). It really depends on what classes you take though. I think if you were seeking a difficult major chem can be harder, especially after physical chem. I’m a bio major, and bio is pretty intuitive to me. I’ve taken a lot of chem classes and it never has the same natural feeling of understanding that bio has for me. Also, to be fair there is ecology and then there is more molecular biology. ecology is practically a liberal art. You shouldn’t get a B.S. in ecology.</p>