Thinking of the primary propellants used for typical rocket launches (such as Hydrogen, RP-1, solid fuel), what are the odors of the exhaust and burned fuel components? I'd think that the Hydrogen would produce minimal odor due to essentially just water being the result, but wondering what RP-1 and solid fuel exhaust would smell like.
So a caveat to this answer; these are qualitative descriptions based on my experience.
LOx/H2: I haven't been close enough to a launch or static fire to say.
LOx/RP1: As Anthony X mentioned, RP1 is highly refined kerosene, so the smell is similar to that of a barbecue lighter. One thing that I noticed is that the smell of gaseous RP1 is significantly stronger than that of the LOx/RP1 combustion products.
Solids: There are dozens of propellant combinations for solids, so I'll just cover the one that I am the most familiar with - APCP. The smell is somewhat sulfuric and foul. After smelling this enough, and getting used to it, it isn't so bad. That being said, this is definitely something you don't want to smell (NO2).