The Wonders of Energy: Why isn't "cold" a thing? How do other compounds, mixtures, and materials make something 'colder' like glycol?

The Wonders of Energy: Why isn't "cold" a thing? How do other compounds, mixtures, and materials make something 'colder' like glycol?

By: Ian Davis

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Introduction:

I'm sad to ruin your childhood, but 'cold' is just a term, and not really a thing in and of itself. I used to thing that 'cold' was just tiny particles shaped like little snowflakes that would make something cooler, however, as soon as I got into middle school, I learned that 'cold' is just the absence of heat. Now I love knowing the "ins-and-outs" of this little definition (including thermal equilibrium don't worry) but nevertheless always had questions about one particular thing, how do certain compounds, mixtures, and materials make something 'colder' and why is that their natural property?

We are used to understanding that if you apply something on a hot area, it just simply makes it colder. This can be in the form of some type of coolant (usually just for cars and their parts if you just search "coolants") but it never really gives us a straight answer unless we are willing to put on a safety helmet and head into page 2 of google.

My Thoughts Before Research:

Now lets add a bit of context, you are probably confused on what I mean about the substances' 'properties' but don't worry I will explain a bit further. The substance of Object A can be applied and keep at a certain temperature (especially interesting at room temperature) to Object B, making Object B lose most of its heat in a substantial amount of time, and I wonder why? Especially if it's at room temp.

So I started thinking, maybe I have to search at the atomic level to start seeing things a little bit more clearly. Perhaps the answer lies within the molecules themselves as in electronegativity or even absence of electrons? So then I proposed theory 1:

Theory 1 - The absence in Object A's electrons/energy level may be the reason it practically pulls the energy out from Object B's surface:

    However as soon as I thought that, maybe problems began to arise. We know that energy and more specifically electrons, can be pretty versatile and jumpy, especially when it comes to a anion or cation molecule/atom or when another atom/molecule comes looking to be friends. But what about solid, rigid, and even crystalline objects that are bonded to each other so strongly you'll need high temperatures to begin to take out the shape aspect of Object B (And yes, we are imagining that Object B is a solid, more specially a metal) and this means that it's not willing to share many electrons when it's: fulfilled the rule of octet, in a rigid crystalline shape, and especially when it's below it's melting point. Meaning that this theory could be a tough one, but I am yet to rule it out since this is before my research.

Theory 2 - Perhaps the Object A is so thin but strong, that it somehow bonds with Object B therefore pulling out energy and electrons with it:

    Oh my, so many red flags. Yes this could be a possibility if you're lucky, but even then it would be bittersweet because if you're using this coolant, then good luck using Object B ever again. But let's try and not be too harsh okay? This could also work, imagine that the application of Object A would be able to pull energy from the main network of Object B's composition and practically share energy with Object A, therefore making it less likely to get excited and hot from well, heat. Nevertheless the problems with this theory highly outweigh the benefits, so I'm just going to go ahead and rule it out.

My Thoughts After Research: 

Okay so let's go ahead and just define coolant: Coolants are a substance usually in liquid or gaseous form, that has high thermal capacity, and low viscosity, they are used to regulate and reduce the temperature of a certain object or system. As much as it gives me good information, this isn't exactly what we are looking for, but what we know now, is that coolants are placed throughout a certain system or place and it picks up heat, cool. But how is it so good at picking up thermal energy from a hardened substance like metal?

Credit and found: https://s3-us-west-2.amazonaws.com/courses-images/wp-content/uploads/sites/752/2016/09/26194945/512px-Metallic_bonding.png

From what we know is that metals are great conductors, meaning they conduct heat and all of that good stuff through its' main composition, and in doing so they get heated up. So then the coolant is introduced, and then it goes throughout the hottest regions and picks up some of that thermal heat and is then pulled up and taken out through a series of gaskets, kinda like a train (more on that later) and therefore we don't see that heat for awhile. 

Now why isn't common chemicals like water run through these systems? Water is really good at stuff like that. Well, it is and it isn't, so let's take a look at the chemical makeup of these coolants; coolants are typically made up from glycol, but more specifically ethylene glycol, propylene glycol, 1,3 butylene glycol, hexylene glycol, diethylene glycol or glycerin. Why? Well that's because glycol is commonly mixed with water to create this ultimate mixture, so that it makes the water's freezing point significantly lower so that during winter times (hence called antifreeze) so the water-glycol mixture remains liquid and readily used to pull heat from the system. Water by itself can easily be contaminated, can freeze during winter, and is not as an effective heat transfer opposed to it's mixture with glycol

Caption: Glycol-Water Mixture Composition

Credit and found: https://blogger.googleusercontent.com/img/proxy/AVvXsEj_qW8htZ6tRqRdOg_UZ5yO5XqvHe3Emwk_1ukKApndPNQGWVFEj5obsOV1ZNT2VVJqtODglECvzv6HZ4hyefSLhqmYAPSDOoMJBpVgcBcSO_E5FhYR3e9_oQS0Q9mMPwHPuG-pTD6YjQf5nVeIId9CpgZxHPYAWKRrrn1QtLNK=

You must also ask, why does something colder get hotter or vice versa? Well that's due to equilibrium, or just "everything wants to be the exact same temp everywhere all the time" pretty much, meaning that when different temperature substances meet, they try to form a common temperature in between them, that is the general majority of the temperature around them. Meaning that when you have a cold ice cream in room temp. you're ice cream slowly adjusts to the room temperature and melts, since it's crystalline solid form, is not supported in that temperature. That can be applied in some aspects to the idea of equilibrium.

Credit and found: http://www.chm.bris.ac.uk/motm/ethylene-glycol/glycoljs.htm#:~:text=Because%20opposite%20charges%20attract%20each,of%20hydrocarbons%20of%20similar%20mass.&text=The%20hydrogen%20bonding%20in%20ethylene%20glycol.

You could also ask, why doesn't glycol melt and have the same problems like water does? Well no worries because all we have to do is look at it's chemical composition and the pressure that it is kept in the system. Though the typical boiling point of glycol is around ~400 degrees Fahrenheit (which is usually below the temperatures of a typical engine) the pressure of the system makes the boiling point of glycol even higher therefore it can withstand a lot more heat, this is why leaks are practically fatal to your cooling systems for various amount of reasons excluding pressure. Ethylene glycol and propylene glycol have hydrocarbon connections throughout it's composition and since these glycol's have such long and stringy molecules, they get wrapped and tangled like pasta without breaking apart therefore making them appear and act shorter, and shorter molecules need more energy to be separated. Opposites attract as we know and since that glycol, specifically Ethylene glycol, have two sides of the glycol that are opposite charges, including the wrapping mess with the hydrocarbons, it gets wrapped harder than those Apple(TM) wired earphones that's been left in your backpack for years, making all the heat and energy to pull them apart, quite immense, therefore the glycol pulls a large amount of heat and energy from it's surrounding to not only achieve equilibrium, but to not be untangled and start to spread out AKA the boiling point.

The Saturated Hydrocarbons, or Alkanes

Name		Molecular Formula		Melting Point (oC)		Boiling Point (oC)		State at 25oC
methane		CH4		-183		-164		gas
ethane		C2H6		-183		-89
propane		C3H8		-190		-42
butane		C4H10		-138		-0.5
pentane		C5H12		-130		36
hexane		C6H14		-95		69
heptane		C7H16		-91		98
octane		C8H18		-57		125
nonane		C9H20		-51		151		liquid
decane		C10H22		-30		174
undecane		C11H24		-25		196
dodecane		C12H26		-10		216
eicosane		C20H42		37		343
triacontane		C30H62		66		450		solid

Credit and found: http://chemistry.elmhurst.edu/vchembook/501hcboilingpts.html#:~:text=The%20reason%20that%20longer%20chain,of%20attraction%20for%20each%20other.

Explained Simply:

Wow, that was a lot right? So my job here is to help of you try and understand the mess of physics, chemistry, and just pure pain all wrapped up in words before this paragraph, no biggie. So let's imagine that coolant and other liquids or gases are like these big nets right? They are going throughout their own cooling system to try and pick out this pesky heat that's troubling everything else, so they go and pick it up and carry it out like the good guys.

Okay I know I know you're not toddlers but that was the best I had, anyways heat bothers these systems so much that they require cooling and help from another source AKA coolants. So once a coolant is applied, it goes throughout a system and picks up the heat throughout the system (by tunnels and holes throughout the main system) and it carries it out. Why isn't the coolant affected? Well it is but it isn't, that what makes it so special. The coolant has a complicated 'make-up' so it doesn't get as affected by heat as much as other things do, therefore it pulls the heat from one place, brings it along like a train to another place and that's what we see as 'cold' or 'colder' even though it may not be 'cold' to our standards.

Sources:

1. https://en.wikipedia.org/wiki/Coolant#:~:text=A%20coolant%20is%20a%20substance,corrosion%20of%20the%20cooling%20system.

2. https://www.quora.com/What-are-coolants-How-do-coolants-work

3. https://patents.google.com/patent/US6096236A/en

4. https://socratic.org/questions/how-do-atmospheric-pressure-and-elevation-affect-boiling-point#:~:text=As%20elevation%20increases%2C%20atmospheric%20pressure%20decreases%20because%20air,less%20dense%20at%20higher%20altitudes.&text=Because%20the%20atmospheric%20pressure%20is,lower%20to%20reach%20boiling%20point.&text=The%20boiling%20point%20is%20lower%20at%20higher%20altitude.

5. https://www.holtsauto.com/prestone/news/what-does-mean-car-coolant-bubbling/

6. http://chemistry.elmhurst.edu/vchembook/501hcboilingpts.html#:~:text=The%20reason%20that%20longer%20chain,of%20attraction%20for%20each%20other.

7. http://www.chm.bris.ac.uk/motm/ethylene-glycol/glycoljs.htm#:~:text=Because%20opposite%20charges%20attract%20each,of%20hydrocarbons%20of%20similar%20mass.&text=The%20hydrogen%20bonding%20in%20ethylene%20glycol.

8. https://wtamu.edu/~cbaird/sq/2016/03/08/is-metal-a-good-heat-shield/

9. https://www.britannica.com/science/glycol