The tips begin at a different place in each module. The advice moves along with the stages of the course.
Chemistry doesn't reduce to physics. It's better to say that chemistry supervenes on physics. In other words, the facts of chemistry are entailed by the concepts of physics. Physics concepts determine beforehand how we get to an understanding of chemistry. Laying the foundation to understand a supervening discipline by first obtaining tacit knowledge of the discipline underlying it is a productive logic.