How are chemistry and recycling related?

Answer 1

In recycling anything--plastics, aluminum, paper--you'll have impurities, such as leftover food, inks, etc. If you want to be able to figure out how to remove them, or how to work around the fact that their presence changes the material properties of what you're recycling, you need some knowledge of chemistry. It really falls more into chemical engineering or materials science than traditional "chemistry," but you still need the knowledge.