What's that smell? This week, Melissa and Jam explore the chemistry of smell. Now a lot of smell science has to do with our physiology and neurology. We'll talk some about that, but the chemistry has to do with the actual smells in the air. What are they? How do they get into the air? How can we detect them with our noses and brains? Why does rain have a smell, and why does it smell good? Let's find out.