These Chemical Analogies are Terrible: Part 1
I decided to go through with writing a final suicide note to chemistry. After my final falling out with the discipline that nourished me for most of my life, a period of brooding introspection showed me a need to give it a proper goodbye - a goodbye I have decided to sign and deliver with a final brain dump of all the awful analogies that have sustained me throughout the years.
“Analogy” isn’t even the right word for it. I’m not even sure that “allegory” fully captures the true delusion that characterized these long, cumbersome stories that I would flash the frontal lobe of my weary brain with. I believe Hitler said that if you tell people something loudly enough and long enough, they will eventually take it to be true. I must have had over a hundred little Hitlers in my head yelling You understand it! Next concept!
These were shameful little guilty pleasures I would retreat to. Nothing gave me more comfort in my college life than closing the unforgiving textbook, stashing away half-finished homework, and weaving a shimmering web of false-understanding.
If you are a chemist, look away
I can’t stress this enough: if you are a chemist, a professional, a researcher, or just a faithful combatant in the war against the perpetuation of ignorance, then for the love of Schrodinger, just look away .
The true professionals among us never need an analogy to embarrass a higher truth. A perfect argument sings truth, just as a perfect design doesn’t need an explanation. Great, elegant solutions should exude their coherent beauty and cut through the darkness like a brilliant, proud lighthouse.
– or, you could just wait for an idiot like me to compare it to something that happened in “The Suite Life of Zach and Cody” –
That being said, I’m writing for pretty much anyone with the aptitude needed to track with an episode of Psyche . This is for the Walmart shoppers and the Jay Leno watchers. My goal isn’t to get you to understand chemistry. There is no shortcuts in doing that. My goal is to show you what you can learn from it.
If you don't normally like science, just give this a try. Believe me - if I can understand this, you can.
What would a molecule do for a Klondike bar?
This week is going to be kind of deep (deep, like Bullet-for-my Valentine deep - or first-week-of-philosophy-101 deep). A fitting place to begin this mysterious journey of exhibition is the most fundamental question anyone can ask: Why does anything do anything? Teachers often make the mistake of beginning with the more sobering and wondrous examples of this question being answered. Why did we drop the Atomic bomb on Japan? Why does the salmon swim upstream to die? Fun for the good students, but we are bad students, remember? We just want to talk about urine.
What would it take to get you to wet your pants in public? Go ahead and name your price. Whisper into the soft glow of your computer the compensation you would need to voluntarily wet your pants in public. Is it a hundred dollars? A single doge coin? A side hug from Jennifer Lawrence? Though some would consider the spectacle of themselves publicly “accidenting” to be priceless, I believe we all have our price.
The party game
Now let us bring in the kind of guy that can ruin any chill party game by recording everyone else’s answers in a spreadsheet. He is probably seated with his new Surface Tablet close at hand, donning a ripe Big Bang Theory t shirt, and vehemently insisting that the Zune player was divinely more innovative than the iPhone ever was.
So Sir Neckbeard wants to enter everyone’s responses to the fun pee question into a crisp spreadsheet, but he complains that the variety of everybody’s zainy compensatory scenarios don’t make for a very normalized data set. There will be no way to get any funless numerical data from the set. He calls the column “ H ”, because it’s the first letter in Heidi Kluhm’s name, for all we know. He demands that everyone translate their answer to a numerical value. People go around shouting arbitrary numbers to scale their response, ranging from 1 to 1 million. But his administrative yammering is silenced by a small, still response in particular.
“Negative ten.” Sir Neckbeard recoils in disgust. Who had the gall to corrupt his dataset with a negative number? The crowd parts, revealing a newborn baby sitting on the floor. Sir Neckbeard crosses his Cheeto-dusted arms and confronts the baby.
“Um, kind sir? You gave me a negative number.” The baby, with uncanny dexterity, furrows an aged brow and nods.
“Of course I did, stupid,” he retorted between the calm, collected tounging of a wad of chewing tobacco. “I was going to piss my pants anyway. That’s what I do. I’m a baby. Make sense?”
The crowd cheered defiantly as Sir Neckbeard tipped his Fedora to the animated baby stranger. Sir Neckbeard relinquished to his Surface to make a very important change to his spreadsheet. He changed the column title from H to Delta H .
Needless to say, this is turning into one weird party. But my bizarre ruined-party-game-saved-by-demon-possessed-baby analogy hopefully succeeds in introducing the idea of the Delta H in chemistry.
Chemists call this enthalpy . If the word means about as much to you as a tribal tattoo, don’t sweat it. Part of me even suspects that this noun was made up just so we can have the privilege of using its sultry adjective counterpart - enthalpic . You can’t say enthalpic too many times. Go ahead. While we are whispering things into the soft, fleshy glow of our computer monitors, go ahead and whisper that one too.
But enthalpy, in lack of an endless possibility of better words I could have chosen, is simply what a molecule would do for a Klondike bar . More broadly, it is what it would take for something to do something. And Sir Neckbeard? He’s certainly based on a true story. There were hundreds of thousands of them that put their broken hearts and throbbing heads together to come up with the biggest buzzkill spreadsheet imaginable. It’s not just for one “what would it take to get you to wet yourself” question either. Modern science has surveyed thousands of molecules most of the bizarre questions that they could come up with, converting them to a nearly arbitrary number.
And the weird, snarky benjamin-button baby? That was just to enforce the reality that some people are going to be wetting themselves later that afternoon whether you offer them money or not. This is why we have to call the value the change in enthalpy - because it’s not always going to be positive.
Here is a snippet of that list. Note that the “questions” are rarely worthy of the party game rotation. Usually, they are something along the lines of “How much would it take to get you to explode into gas?” Chemists are weird sometimes.
Figure 1: What would it take to get me to make myself? This survey was hardly worth the Panera gift card.
Also note that when your are only answering questions for yourself, you are kind of limited in what questions you can put in circulation. In all the individual examples, the questions usually can just be “How much to absolutely destroy yourself” or “How much to just make yourself from scratch”.
kipping all the important overhead work of applying this to reality, we can steal away and learn some more important relationships having to do with enthalpy. Imagine you are asked another party question. How much would it take for you to kiss your cousin? Upfront, you would expect the answers to be universally high numbers. But Sir Neckbeard has left and there have already been enough Natty Lites in circulation to loosen things up a bit. Most people would hate to kiss their cousin. Some people have cousins that wouldn’t mind it (Europeans, probably). Some people admit in a beer-soaked confessional that they would love to kiss their cousin. Things get complicated.
But for the spreadsheet we are making, we don’t really have a social responsibility to reflect any of the psychological travesties at bay. The way I see it, you just take the Delta H for cousin 1, the Delta H for cousin two, and add them right up. If you get two normal God-fearing cousins, there you go - no kiss. That Delta H is high enough for Baseball and Apple Pie to feel safe again. If you get a cousin who is really into it and a cousin who is more of a "left-leaning conservative", you may or may not get a kiss. If you get two cousins that are wayyy into it - well, just call a cab. That means this party has gotten way too Craig’s List for your taste. If you leave now, you might even be able to share a cab with man-baby.
The underlying principle, setting all kissing-cousins aside, is that the net enthalpy for a reaction is simply the sum of enthalpies .
We said all that before, remember? Just add up the Detla H ’s. The same applies for asking in multiples, fractions, and all types of weird abominations and perversions of the analogy that will not be discussed in this blog.
What about not peeing on yourself?
So you are sharing a cigar with man-baby and waiting for your cab when you see Sir Neckbeard triumphantly emerge from the bushes to once again confront man baby. He waves his revised spreadsheet in front of man-baby, who gives it a careless glance through a thick wall of cigar smoke.
“I have revised the data set!” squeals Sir Neckbeard. Man baby stiffens his leathery jaw, demanding an explanation with his steely eyes.
“The new question is thus: *What would it take to get you to not pee on yourself.” sneered Sir Neckbeard.
Man baby pauses to contemplate the new thought. To not pee on himself… “Well… I guess it would just be the opposite of whatever I said for the other question. Since I was planning on peeing myself later, it would be kind of a hassle to stop me from doing it.”
Neckbeard shakes his jowls in celebration. “AHA! That makes your answer positive . It is once again a normalized data set.”
Though you are in the middle of wrestling tobacco induced hysteria from whatever hardcore Cuban contraband Man baby lit up for you, you manage do communicate one small incongruity you noticed with Neckbeard’s new data set.
“Then wouldn’t everyone else’s number have to be negative?”
Sir Neckbeard casts down his Surface , shattering it on the patio. He bows his head in fatal defeat. You don’t get a chance to relish in your victory, sadly, because your are tripping like nobody’s business on shady Cuban tobacco. But man-baby is faithful spread the word to everyone in the house. They all agree that if the question were reversed, their answers would be negative - since none of them were planning on wetting themselves later.
The principle: whatever a molecule has “submitted” as his answer to the party question, the value can just be negated to reflect its answer to the reversed question.
Building an equation
So we have actually been building an equation. It’s the equation that predicts if something is going to do something. Just as we assigned what a molecule would do for a Klondike bar the name Delta H , we can take a step back and take a look at the broader question, of which I will paraphrase by quoting Ice T - Is it about to go down?
Ice T’s question isn’t so much concerned with the molecule’s answer in particular, although that will help with the final answer. Ice T is more concerned with the public self-wetting as a phenomenon - witnessed alike by the wetter, the guy who paid the wetter, and upwards of 100,000 YouTubers.
The answer to Ice T’s question is assigned the letter G . Much like our letter H , the number reflects how likely it is about to go down . A negative number means it most certainly is, while a positive number means it probably isn’t.
As of now, we have only pieced together the H and the G , making our equation rather simple:
Ice T’s question is only using what is in Neckbeard’s spreadsheet, or the sum of H’s from all the parties involved in the public stunt. Next week or so, we will cover what else we need to consider in answering Ice T’s profound question, which will undoubtedly involve a return to the worst Craig’s List party you have ever attended.