Five Assumptions for Ideal Gases
The Ideal Gas Law combines Boyle's Law, Charles' Law, and Avogadro's Law in one simple, memorable formula: PV=nRT. The major flaw in this formula is so obvious in its name that it's almost funny when you finally realize it -- the law only fits data for ideal gases. It's a perfect model that we can use to predict the data we'll get when variables are under our control. It's the only way we know how to make sense of the world. Yet, real life is hardly ever so easily explained, as this model often only holds true when gases are at low pressures and/or at Boyle Temperature.
I could get into the details of where the Ideal Gas Law fails, and the other models (like Van Der Waals) that scientists have developed to try and account for problems of attractive forces existing between molecules, or the volume of the molecules themselves -- but you can learn all of that in a physical chemistry class. Instead, I'd like to share with you poetry inspired by studying chemistry -- in other words, the world my mind wanders off to sometimes when I need a break from all the integral calculus.
1. Gas particles are in continuous, rapid, random motion.
The trains rush by, gray
Blurs against graffitied
Concrete walls, rattling
On the tracks that hold
Them on strict routes, but
They never seem to be on time
When they finally
2. There are no attractive forces between particles.
Gravity is just attraction between two bodies
But gravity is the weakest force when you consider
Electromagnetism that holds all of our cells together
And they say that opposites attract
(Although positive and negative are arbitrary constructs)
And I thought I would be repelled by you
But sometimes magnetic fields can be induced
And the force that attracts me to you
Is so much stronger than gravity
3. The gas particles are far away from each other relative to their size.
My brother was born in the Year of the Dragon
If you consider 2000 that year
Although his birthday fell before the birth
Of the new lunar cycle.
And the only thing I know about mahjong
Is that the tiles my grandmother played with
Feel cold in my hands.
And all I can write in Chinese
Is a name, my name
That I don't ever use.
And fortune cookies I got with my dinner
Told me that "a thrilling time is in store"
And I wondered about the time before now
If I could trace my ancestry back across an ocean
I've only managed to cross once in my lifetime
What would I find of a culture I have only seen glimpses of from this side?
4. Collisions between particles and between particles and the container walls are elastic collisions.
We are like a rubber band
s t r e t c h
Every time you pull away
You're forced to snap back to where we were before.
But every time you pull a little farther,
I feel us
5. The temperature of the gas is proportional to the average kinetic energy of the molecules.
The arrows in chemical reactions are deceiving
Because you think reactions only go one way
But actually they can go both forwards and backwards
They just tend to go the way that leads to a decrease in energy,
The way that leads to stabilization
We used to be on fire
Isn't that how all good stories start?
But the fire burns out once the oxygen's gone
We've only been going one direction
A combustion reaction
And I think someone forgot to teach us
That potential energy
Ends in repulsion