I’ve been brushing up on aerosols lately. In the course of job hunting, I found an open position for an aerosol researcher at one of the DOE national labs (looking for: chemist, chemical engineer, or atmospheric scientist…take three guesses for what they’re working on). My first instinctual answer to “What do I know about aerosols?” was a whole lot of nothing. Spraypaint, right? And PAM? Somehow I doubt that’s enough for a successful application.
But the more I thought about it, the more I think I actually know, or at least could translate from parallel science, about aerosols. I mean, they’re essentially a suspension of solid or liquid particles in a fluid right? Here, of course, I’m using the broader-than-my-elementary-school-lessons and defining a gas as fluid (the 10 year old that still lives in me is shouting “Nuh-uh! Three phases: solid liquid and gas!”).
Because my brain has been in science writer mode lately, it started working through analogies. How could I illustrate an aerosol? Then it hit me – there’s already a not-so-terrible hands on macro-scale analogy for the micro-sized aerosols:
If you’re old enough to remember Orbitz (and hopefully not cosmopolitan enough to have tasted it), you’ve seen a hands on model of an aerosol! If you don’t remember, be thankful, and then take a look above. There it is in all its glory! A handful of small, squishy, sweet particles dispersed through a fluid (which we can pretend is the fluid of air). That right there is a simple proverbial ball-and-stick model of clouds, perfumes, spray paint, pollen, and volcanic ash. Of course, the difference between a cloud, a dust storm, and Lady Gaga’s blood and semen perfume is all in the details. There are some chemical details (how the particles or droplets interact with another and their environment, often through hydrogen bonds or van der waals forces), some physics details (gravity, the flow of the fluid/air around the particles), some geometric details (how closely those particles are packed together, how they’re shaped). But for a simple model? It’s all in one debatably tasty beverage.