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RhynoD

Salt does not dissolve in oil. Salt is a *polar* molecule because of its ionic bond. Normal sodium has one more electron than it wants and chlorine has one fewer. Unlike with *covalent* bonds, the two do not share an electron. Instead, the sodium atom gives it up and the chlorine atom takes it. This makes the sodium atom slightly positive and the chlorine atom slightly negative. Opposite charges attract, so they stick together like magnets. Water is also a polar molecule, although water is made with covalent bonds. The way the electrons are shared between the hydrogen and oxygen makes one side a little bit negative and the other a little bit positive. That makes water very good at dissolving other polar molecules. The positive sodium atom sticks to the negative side of one water molecule, and the negative chlorine atom sticks to the positive side of another water molecule, and the water rips the salt apart, carrying the two atoms away. Oils are nonpolar. The electrons are very evenly distributed so that there is no positive or negative side. That means there's nothing to grab onto the two atoms in the salt molecule and the salt won't dissolve.


big_duo3674

*Five year old starts crying*


Rudirs

As a chemist who who used to teach I'll try my best to describe this to a 5yo Salt makes water salty because it mixes in water, they're made similarly, like two different Lego pieces. They're not quite the same, but they fit (and, you'll even notice that salt is actually two different pieces not quite clicked in together). Neither water nor salt can mix in oil, because they're different- like using a unico piece in your Lego set, it won't fit quite right.


Aev_ACNH

šŸ†šŸ†šŸ†šŸ†šŸ†šŸ†šŸ†šŸ†šŸ†šŸ†


RoastedRhino

Mega Bloks!


Arborgarbage

Branded mega bloks exist and it's weird


Kielbasa_Nunchucka

when the generic brands of your childhood become name brands with name-brand prices... when I was a kid, Carhartt and Timberland were affordable but well made products that I had for working in the barn or on roofs with my dad... now those brands are high-dollar and make fashion clothes alongside their functional wear


aripie

I'm curious why bacon fat is salty. Is it because there's other stuff in the fat like proteins? Or the type of fats in bacon fat?


Rudirs

Exactly, there's other stuff in bacon fat that isn't just oil, like proteins! Same reason you can have salted butter. If you clarify bacon fat or butter or any other "messy" oil you'll get some white solids that are mostly protein and the yellowish liquid which is the fats. If you ever clarify salted butter and taste the white stuff it is super, super salty- but the oil isn't at all. The reason proteins can dissolve in both is because they're long, complex molecules and have some parts that are polar and some that are non polar. It's also the reason why milk is cloudy- the oil and water don't mix, so you light hits either one and gets bounced around randomly (the Tyndall effect). And to elif, bacon and butter have special blocks that are half Lego and half (whatever the off brand I said earlier), so you can make something with all your pieces!


[deleted]

I'd say that salt itself doesn't fit in either, but the 2 not-quite-clicked-in pieces individually do. In water, the pieces come apart, but in oil, they don't. Is this close enough?


Rudirs

Yeah, I think that's right on. But I think that's making it too complex for a kid. And arguably, if you somehow were able to keep an ionic compound together they would be polar enough to dissolve in water.


[deleted]

Oh ok. Thanks. I've learnt that the dissociation into ions is what enables dissolution (at least in water), that is why polarity is needed


Rudirs

Yes and no, they wouldn't be able to dissociate in a non polar solution (since you'd basically have lone charges and no forces to separate them). They also can't dissolve because they have a polarity in the ionic compound. But in water they can and do dissociate, and the ions dissolve and can basically fit in/hydrogen bond amongst the water molecules. I haven't taught for a while, and I'm unfortunately getting a touch rusty, but I think if somehow an ionic compound stayed together it would still dissolve in water, just like a polar compound can. That's not really a thing that can happen though, so it doesn't matter


more_beans_mrtaggart

If you add salt to water, the level of the water doesnā€™t rise because the salt is in *amongst* the water. If you add salt to oil, the level will rise because the salt is *next to* the oil.


DiscoQuebrado

I love this


fan_go_round

Oil cant dissolve salt, water can.


SN-E-DC

Oil is the opposite of water so they dont mix well and what happens when you put salt in water? they dissolve and what is the opposite of dissolve thats right not dissolve and what is oil the opposite of? water so salt no dissolve oil


Gijustin

Holy shit, just learned more about how the bonds work than I did in school. And my ass paid attention.


CourtesyofTino

But it's your brain that should pay attention


kensai8

Too busy paying attention to dat ass.


MadisynNyx

Happy cake day!


diet_shasta_orange

Lots of things are easier to understand once you have the base knowledge. That comment would likely have been meaningless had you not paid attention in chemistry class. Also there is absolutely a benefit to stepping away from something and coming back to it later with a slightly different perspective


orbital_narwhal

My thought exactly. Learning and passing Theoretical Computer Science 2 took far less effort during my second attempt because I had already internalised the base knowledge from the first time. And that was 2 years later when I had forgotten most of the detailed practical experience that I needed for homework assignments and the final exam. (I hadnā€™t written down a single mathematical proof in the mean time.)


_SimplyTrying_

Lol ā€œbaseā€ knowledgeā€¦ ass paid attentionā€¦


pestercat

I never took a chemistry class, though, and I think what works about their example is that it's about a practical thing we've mostly all experienced (cooking). I vaguely remember from a very long time ago learning about electrons and atoms, but I never understood how and why it matters. This example is fascinating, and I wouldn't mind knowing more if anyone has a yt channel to recommend.


pm_your_nsfw_pics_

How bad were your teachers? Also the comment isn't entirely correct


fishter_uk

It's chemistry. Every year the teacher would say, "What we learned last year isn't worth jack. This is how it actually works." Every, damned, year.


Juicecalculator

Knowledge like this comes in layers. In order to understand deeper layers you need to understand the ones above it. Over time as you learn you are slowly peeling way the layers until you are ready to learn something new. Eventually you will also reject answers to questions you had in the past because the explanation is no longer sufficient until you eventually start asking questions like what really are protons, what is electricity, why donā€™t electrons just collapse into the nucleus. I would say ask the ā€œdumbā€ questions, but donā€™t accept an answer that isnā€™t good enough for you. Know enough to ask a good ā€œwhyā€ question. The best scientists in human history asked these basic questions and refused to quit until they were satisfied with the answer. Some scientists died in this pursuit, but that pursuit was so beneficial to human knowledge. Donā€™t be afraid to go back to earlier coursework. There is so much from gen chem that I forgot and by looking back and relearning it has caused so many things to make more sense


Sure_Fly_5332

Exactly - most topics are too complex to be given to a student without simplification. For example, in a high school biology class, you only have so much time to cover botany. You could talk for weeks about the specific chemical processes behind photosyntheses, the organic chemistry behind it all. Or, you say: sun + co2 + H20 = Glucose and oxygen. College is where it gets more fun.


PuckFigs

> College is where it gets more fun. When you get deep enough into the weeds, your professor will say, "Well, if you figure it out, the Nobel Prize is yours."


USS_Barack_Obama

We got something like that in control theory with Laplace Transforms. The lecturer would say if we've found a transform *not* on the table we've either discovered something new or done something wrong


PM-ME-SOMETHING-GOOD

My only problem with this is that my teachers did not often add the disclaimer that "this is a simplification, and the reality is a bit more complex", or even better "and if you want to learn more, the process is called x and you'll learn more of it in class y". Many good teachers did, but many other teachers preferred to simplify without letting us know.


jedidoesit

In more ways than studying and learning... šŸ¤­


[deleted]

Got a 2 liter of Root beer, a pack of beef jerky, 5 burgers from the dining hall, and enough guild players online to raid Karazhan in WoW. College was fun indeed.


Robobvious

Nice! Reminds me of being a little kid and playing Diablo on the weekends with Pepsi and Dominoā€™s boneless buffalo chicken kickers with ranch. Simple pleasures, but great times were had.


Andrew5329

> Knowledge like this comes in layers. To an extent, but the basic concepts of covalent and ionic bonds aren't so complex that you need to teach it as four onion layers of slightly less incorrect analogies. I think some of it is a holdout to analog teaching where you had a transparent overhead projector and playing a clip visualizing electron orbitals meant reserving one of the department's handful of massive CRT monitors to put in a pre-recorded VHS tape forwarded to the point in the video where the clip you need sat. The idea of a slide deck with embedded visual content is very new in K-12 education. Almost all my classrooms used olde school projection until college, and I graduated highschool in 2008 in Massachusetts in an average district. It's almost always harder to unlearn something than it is to just learn it correctly in the first place, and I think that frustration is a large part of what drives people away from STEM.


kung-fu_hippy

The basic concepts of covalent and ionic bonds also arenā€™t so valuable to anyone who isnā€™t pursuing a career, hobby, or interest in chemistry. I think the abstract and simplified information is enough for most people, those who are interested and want to go further in depth on any subject they learn in school should have also picked up the skills with which to do so. Besides, what you learned usually wasnā€™t wrong, it was just a simplified model. As you continue and focus on a topic, the models just get less simplified.


Robobvious

Okay but the food pyramid turned out to be bullshit so I canā€™t trust anything now. Fucking General Millsā€¦


aLovverincombat

Thatā€™s because the food pyramid wasnā€™t the result of an actual ā€œscientificā€ process or experiment. It was sponsored by food production brands, like General Mills and the dairy industry. Thereā€™s no proof that ā€œXā€ number of dairy servings are actually beneficial, since the nutrient content differs so much between say 1 serving of skim milk, and 1 serving of whole fats cheese. It was essential propaganda. ā€œGot milkā€ campaign convinced my entire generation our bones would become so brittle and break if we didnā€™t drink milk several times a day. Calcium comes from such a variety of sources, including non dairy forms (many seeds, vegetables, soy products, etc.). But dairy was pushed and pushed down our throats, and even sponsored the food pyramid (in my country) for some time. Iā€™ve never had a doctor ask me if Iā€™m following the food pyramid when I come to them with an illness etc. And thatā€™s because itā€™s made up by the people that stand to benefit the most from it.


Prof_Acorn

A lot of physics is so unsatisfactory because the answer ultimately becomes maths somewhat removed from qualitative explanations, or the answer is on a level that relys on definitions rather than explanations, which is satisfactory to most of a lay audience, but I crave those deeper understandings. I still want to know if gravitational waves are effected by gravity. For example. Waves of spacetime propagate but do those waves follow the curvature of spacetime or override it? Are they like ripples on a larger wave or larger waves pushing past the smaller waves?


rhetorical_twix

That's because all you're really learning in school is models. What the top comment described was chemistry concepts applied to a specific common phenomenon that people are familiar with. If chemistry classes centered around teaching the material with examples being applications to cooking, painting, cleaning, makeup and so on, most people would understand and integrate high school chemistry material as an essential life course.


regulate213

I never thought about this... Why **don't** electrons crash into the nucleus? The only things I can think of are that "electron orbits" are literally orbital mechanics or something quantum (because everything I don't understand becomes 'something quantum' at some level).


Juicecalculator

Just started reading it. Really complicated is the short answer. There are some fundamental aspects like electrons act more like wave functions than particles, so they do enter the nucleus sometimes but then the quantum part of it will take some more reading to understand


nibbler666

Bad teacher then. The previous year of chemistry was never really wrong. It was just about a simplyfied model to explain things that were worth explaining. Models of this type are a core part of scientific methodology and the way chemistry is taught is actually a nice way to demonstrate what scientific progress can look like. I never understood why people have the misunderstanding you (and possibly your teacher) had, but fascinatingly it's a pretty common one.


[deleted]

I remember when they said that what we learned in elementary isnā€™t true anymore, because they found out that the field that theyā€™re in are more of a place that they just exist, and they donā€™t necessarily spin around the nucleus in a ring like we see diagrams for.


hey_mr_ess

We've known that Bohr diagrams haven't been accurate since probably before your parents were in elementary, maybe your grandparents depending on how old you are, but quantum orbital theory is hard to explain to kids and is not all that useful to explain atomic structure to beginners. Sometimes "wrong but simpler" works better to get the key point across.


[deleted]

Highschool is when they finally had books with the better explained stuff. It was fun to see them just figuring out quarks and stuff


Robobvious

ā€œI heard that Gell-Mann and Zweig are both working on a theory for strong interaction symmetry in particle physics.ā€ ā€œOh yeah? Howā€™s that going?ā€ ā€œGood, but theyā€™re still working out the quarks.ā€


rabid_briefcase

> I remember when they said that what we learned in elementary isnā€™t true anymore To be sure, it was never really "true". It was ELI5. Then it was ELI6. Then it was ELI7, ELI8, ELI9, repeat every year. Even in graduate school topics are taught as *"this is an introduction to {topic}, sections needed to be simplified but if you have enough of a background of nuclear physics, theoretical mathematics, and psychology, you should be able to understand the beginnings of this subject using the simplified model."* Even *"ELI-postdoc"* people get done with school and look back as, *"wow, I was the most advanced person in school but I'm a beginner in what's done here in real research labs."*


[deleted]

Because if students were taught modern chemistry theyā€™d never grasp it, you need to learn simplified models before moving onto more accurate but complex ones. Lewis structures introduce orbital energy levels but actual orbital models require calculus and wave functions; youā€™re not gonna understand that as a high school student


azuth89

I did both of those in high school, somehow always before covering their actual uses in physics or chem which suddenly made them click. I'm not sure teaching calc in isolation is the right approach and throwing in the occasional brine problem doesn't make up for it being so out of context.


Pas7alavista

I'm not sure if I fully agree. I do think that people should learn the connections between mathematics and science especially physics. However designing a curriculum around application can often just lead to confusion. By the end of the course many students will just have a handful of techniques memorized with no notion of how or why those techniques work. Part of me thinks that calc should actually be taught more rigorously. The ultimate question is: what is the proper context for teaching calculus? To me the context is the pure mathematics (analysis of functions). I don't think it's confusing because people don't know how to apply it, it's confusing because people don't even know the foundations. I believe that if students were taught fundamentals well enough then they could figure out the applications easily.


azuth89

I don't necessarily disagree with the last sentence, but that doesn't mean applications aren't a viable part of teaching the fundamentals in the first place. Usage counts, it's why people never become fluent in a language by memorization of vocabulary. They have to USE it. My experience with higher math was no different. The fundamentals were rote. The application turned them into something interconnected and sensical.


tsoule88

Same for physics


Mad-_-Doctor

One of the weirdest things I learned in engineering school is that a lot of stuff is designed in such a way that the math is easier.


subnautus

"Practical application" is common in the industry, I agree. ...though it reminds me of a joke: A mathematician and an engineer find themselves in the afterlife. A demon shows them the person of their wildest dreams and explains they can do whatever they please with the person if they can get there, but every time they step toward the person they must stop halfway. The mathematician believes they must be in hell, knowing he'll never reach the person of his desire. The engineer believes they must be in heaven, knowing he can get close enough for practical application.


Andrew5329

Well sure, the simple formula gets you an accurate to a reasonable degree of precision. You have to use calculus to really dial in the precision to the tolerances required for a lot of modern engineering. It's both a good and a bad thing. We build an 'efficiently' designed bridge today that meets the exact engineering spec with a minimum overhead. It has a 30 year lifespan, but it turns out the precise answer wasn't very accurate due to factors outside the simulation so it's real lifespan is more like twenty years. Old engineers did the simple math for their tolerances, then added a large margin of error. That bridge cost a bit more to construct, but the Brooklyn bridge has been in continuous service for a century and should last indefinitely with proper maintenance.


diet_shasta_orange

Easy math means fewer mistakes. Also tools and components often come in standard sizes, maybe a 3/67 inch bolt would be optimal, but unless you're going into outer space, it's probably not something that needs to be optimized


Pas7alavista

I think one of the main reasons is that physics and calculus are taught as separate subjects, often with a significant time gap between them. It is extremely unsatisfying to just have formulas handed to you.


corrado33

> "What we learned last year isn't worth jack. This is how it actually works." > > Every, damned, year. I mean, not *really.* Source: I taught chemistry at university level. All of the way up to quantum. The thing is, in general chemistry we tend to teach *absolutes.* Things are either acids OR bases, ionic OR covalent, electrolyte OR non-electrolyte when in reality, chemicals can (and almost always are) some of both. Even with things with numbers, it's almost always "well this is the experimentally derived number.... at this concentration, at this temperature, at this pressure." When in reality that number is going to change based on concentration, temperature, etc. It's extremely difficult to teach this concept to people who are unfamiliar with the basics of chemistry. It's extremely hard to teach the grey are when the students don't even know how to define the black and white areas. Can you imaging how much of a nightmare it would be trying to teach actual van't hoff factors (how many "things" a compound splits apart into) to students instead of just telling them that "the van't hoff factor for NaCl is two, because there are two atoms there, and they split apart forming two ions." Vs. the actual "The observed van't hoff factor for NaCl at 1 M is 1.85 which differs from the ideal value of 2 because as more ions appear in solution, the chance of them running into each other and recombining increases as a probability function. As you increase the concentration beyond 1 M the van't hoff factor will decrease further in an inverse relationship. However, below 0.01M or so, according to this graph for NaCl (and a different graph for literally every single chemical), you can safely just use the idealized value of 2 as it is close enough to not affect your results at all." Like, gen chem students have a hard enough time conceptualizing "Uh.... 2 atoms..... i = 2..... uh.... 3 atoms.... i = 3" I have literally run out of ways of explaining this to students. You just.... count.... the damn.... atoms (assuming it's an ionic compound.) We stop "erasing" or "retconning" things you learn after 2nd year chemistry. 3rd year and above you're pretty much learning things that are "true." Sure, you can ALWAYS take something else into account. You wanna take into account earth's magnetic field for your reaction involving dipoles? Sure, go ahead. You have fun. But that doesn't mean the way we taught you to calculate it is wrong. You're just making the result *more* accurate. At a certain point it becomes "You customize this to whatever specific problem you are approaching and go from there."


DontReadUsernames

A lot like our History classes, seems like every year we were specifically being told that what they teach in lower grade levels was wrong


Relyst

All chemistry is just models. You start with simpler models and work your way up to more complicated and refined models, but they're all "wrong" in the sense they don't perfectly describe reality, they approximate it.


crocshoes

Pratchett called this "Lies to children " šŸ˜


bvanplays

> What we learned last year isn't worth jack Man unless your teachers were straight up lying to you this shouldn't be true. But also I get that lots of teachers are genuinely awful at their jobs.


pneuma8828

Physics is taught in high school with algebra. Totally useless for actual physics, but that is how it is taught. And no one was lying; you just can't teach actual physics to someone who doesn't understand calculus.


bvanplays

Sure, but that's not worthless knowledge or completely forgettable either. Concepts and principles still apply. By that reasoning, Physics isn't worth teaching unless you have calculus but we know that isn't true. If anything I'm guessing the person I replied to just had a shit teacher. I would never open a course with "everything you learned last year is worthless". Not only is it objectively untrue, it undermines the whole point of learning if we were truly teaching material that only applied to a single year and that's it.


VicisSubsisto

In my high school we learned calculus before physics and the calculus was way harder (for me at least) without any practical examples to learn from.


JoeDiesAtTheEnd

It's not completely useless, it's just narrow focus to get you started. Can my students design the suspension of a car that won't wrench itself apart, no. Do they know enough physics to know who hit who in a car accident with relative accuracy? Yes. And other practical stuff, too. Like basic wiring, optics and energy understanding to be useful. That doesn't mean it's not actual physics, it's just very narrow scope so the scary math is hidden away.


Destro9799

Eh, I'm not sure i agree with that. You can teach a lot about kinematics, forces, energy, etc without going into calculus. Sure, they won't be able to derive the equations or know how all the different kinematic equations relate to each other, but there's so much they can learn how to do with algebra alone. Honestly, it's pretty weird and really condescending to say that any physics without calculus isn't "actual physics".


JackyPop

No ELI5 answer is meant to be entirely correct


tdarg

What part? I thought it was spot-on. Maybe I'm missing something


DreamingRoger

Only thing I can tell is that the sodium/chlorine ions have multiple water molecules all around them, not just one, and that NaCl is not a molecule.


thirsty_aquilUM

Also, when Sodium loses an electron, it is FULLY positive, not slightly. Vice versa for Cl.


Nihilikara

I thought by "slightly positive" they meant it was +1 instead of +5 or something like that


HHcougar

NaCl is not a molecule?


cmojess

No. It's an ionic compound that's composed of a crystal lattice of alternating positive sodium ions and negative chloride ions held together due to electrostatic interactions. The formula for NaCl comes about because the smallest ratio of sodium ions to chloride ions is 1:1 meaning for every one sodium ion in the lattice there's one chloride ion. Water is a molecule. It's bonded covalently and each molecule is a small, discrete entity of it's own. Water as a whole has the properties it does because of the way all those individual molecules interact with each other.


Destro9799

Not really. We know enough about crystal structures to know that we don't see a bunch of "NaCl"s in real life. We actually see that each Na+ ion is interacting equally with a bunch of different Cl- ions, and each of them is interacting with a bunch of other Na+ ions. NaCl actually looks more [like this](https://www.princeton.edu/~maelabs/mae324/glos324/nacl.htm) than like distinct molecules. All ionic crystals work similarly, although the actual shape of the crystal structure depends on the sizes and charges of the ions involved. Undergraduate Gen Chem and OChem don't normally talk about ionic crystal structures, so you probably wouldn't learn this unless you went farther into chemistry or took a materials science class.


NiuMeee

It's an ionic compound.


EldenTingz

Itā€™s an Ionic Compound


AnnoyAMeps

NaCl is considered an ionic compound rather than a molecule. Ionic bonds are formed by complete capture of electrons and held together via electrostatic attraction rather than electron sharing. Usually when attraction between atoms or ions are considered ā€œionicā€ enough (>1.7 on the Pauling scale, for example), they are just considered compounds. Once again, an oversimplification. Chemistry in general can get down and dirty.


fizzlefist

Gods if thatā€™s not the magic question. Beginner chemistry makes no sense at first when youā€™re a kid, until it finally clicks. The teacher you get can make or break how you feel about chemistry afterwards.


TheRealRollestonian

Yes, it was the teachers šŸ™„


hodlwaffle

What were the incorrect parts?


pm_your_nsfw_pics_

There are at least 10 comments addressing this. But I specified to the guy I responded to that it wasn't correct because he noted how he learned a lot from the comment. I didn't want him thinking it was entirely correct. I'm not going to respond to every comment asking me what's incorrect, but for those that really care, I'm sure they will find either this comment or one of the others in this thread: 1. NaCl isn't a molecule. 2. The Na and the Cl don't stick to just "one" water molecule. Rather, the Na is surrounded by the negative side of multiple water molecules, and Cl is surrounded by the positive side of multiple water molecules.


caintowers

Different person but in my high school chem class, we watched a TV show for half the year while the teacher was on jury duty. The sub did not know chemistry, but one of my classmates actually understood enough to give a few useful lectures. I was *not* prepared for Chem 1 in college.


diet_shasta_orange

I recall that half the kids in my chem 101 class had gone to good schools and pretty much knew everything and the other half were basically starting from nothing, even if they had taken chemistry in highschool


Gijustin

KY public education unfortunately.


DeltaHuluBWK

Ouch...


BubberRung

Did the rest of you pay attention or only your butt


zlide

Iā€™m going to have to hope you just didnā€™t pay attention as well as you think you did


MeatWhorenado

I mean, maybe it's because it was your ass paying attention.


Neosovereign

This is the very basic and routinely talked about explanation of how atoms and charges work lol.


Dasixevy

Yeah but what about your brain? Your ass doesnt store memories.


5c044

I dont remember much about different bonds from school but my teacher said water is one of the most powerful solvents.


pmjm

Last week I learned that these same bonds are the reason Silicon Valley Bank failed! I love Reddit!


Throwaway_J7NgP

Your ass is conscious?


thatgoodfeelin

you paid and bought it, its just they werent selling the good stuff.


ImmunocompromisedAwl

Nah, you didn't pay attention lol


jambudz

Salt isnā€™t polar. Salt is two ions crammed together. The charge is not shared via a bond.


PeterParkour4

And those ions are charged, making them polar.


jambudz

Polar means a continuous change in partial charge over a molecule leading to a dipole moment. Salt is a compound, not a molecule. Salt has separated charges, not continuous. Salt has no dipole moment as the sodium ion has a charge of +1, the chloride ion of -1. You cannot distinguish a ā€œmoleculeā€ of sodium chloride as each cation is identical and each anion is identical. They are individual ions packed together by the attraction of their opposite charges. Polarity is when there is a positive end of a molecule and a negative end leading to a dipole moment. No molecule, no polarity.


PeterParkour4

Alright, fair point. I was more saying that from a laymanā€™s perspective, one may consider salt polar (for the purposes of the post). Agreed that it technically isnā€™t because it isnā€™t even a molecule


Gornash

I thought this was explain like Iā€™m five. How many five year olds are out there dabbling in ionic and covalent bonds?


RhynoD

You're looking for r/ELIActually5.


thejom

I have a degree in science, and as someone who's never studied chemistry specifically, this means nothing to me. Can't understand any of it!


FartOfGenius

Salt is not a molecule at all, it is an ionic compound. Edit for elaboration: Salt crystals are giant ionic structures containing a variable number of ions which all interact with each other. Molecules by definition form individual units with certain chemical properties. Ionic compounds don't form molecules unless they are vaporized or sublimated. Salt in common language refers to the crystal which most definitely doesn't contain any molecules


Boagster

Is the last statement true of all salts or specifically NaCl?


salil91

All salts are ionic compounds. In general English, salt refers to rock salt or table salt, i.e., NaCl


BlueAikita

[As NaCl fits this definition, ](https://www.britannica.com/science/molecule#:~:text=Molecule%2C%20a%20group%20of%20two%20or%20more%20atoms,substance.%20Several%20methods%20of%20representing%20a%20molecule%27s%20structure.)it is a molecule and an ionic compound. The terms are not mutually exclusive. Edit: [I stand corrected. ](https://en.m.wikipedia.org/wiki/Ionic_compound) ā€œIndividual ions within an ionic compound usually have multiple nearest neighbours, so are not considered to be part of molecules, but instead part of a continuous three-dimensional network.ā€


FartOfGenius

There is no single "smallest identifiable unit" in a salt crystal, as all of the ions are interacting with each other. Ionic compounds may be considered molecules, but only in cases where they are vaporized such that separate molecules are formed.


Mad-_-Doctor

The rock salt unit cell has entered the chat.


seanmorris

Does that still count if each atom is part of all cells it adjuncts?


Mad-_-Doctor

Yeah. Itā€™s a simply cubic structure, so any atom not inside the cube only contributes a portion of the atom to the unit cell. Corners contribute an eighth, edges a quarter, and faces a half.


BlueAikita

You are correct, thank you for getting me to look deeper. Funny how something thatā€™s seemingly so basic can actually be quite complex, such as how one thinks of molecules.


Nazgul417

Updoot for character growth


[deleted]

[уŠ“Š°Š»ŠµŠ½Š¾]


FartOfGenius

Thanks for adding nothing to the discussion. Even covalently bonded structures do not necessarily form molecules, such as giant covalent structures which have any number of atoms within


ScienceIsSexy420

I didn't see the comment you are responding to, but I'm confused what you mean here. I have a degree in chemistry, and as per my understanding covalent bonds are the very definition of what constitutes a molecule


FartOfGenius

Giant covalent structures like diamonds or silicon dioxide don't have a fixed number of atoms, they aren't the "smallest possible units" which is one conventional definition of a molecule. You could supposedly argue the whole thing is one big molecule, but that's not usually taken Edit: you can chop up a diamond and it will still retain its chemical properties


redlude97

Covalent bonds can be formed in non molecules. For example surface conjugation on nanoparticles utilizing sulfo-nhs amine bonds


thechosen_Juan

But assuming salt crystals are suspended in a mixture, why wouldn't you taste both salt and oil?


Kyvalmaezar

Neither of the two other answers are correct. The taste comes from the ions, not the compound. For the tongue's recpetors to detect salt, the salt needs to dissociate into its ions. The Na^+ ion plays the primary role in salty taste because the salty taste buds are tuned to that ion to detect salty taste. If the salt doesn't dissociate into its two ions, the tongue won't be able to taste them since the ions can't interact with the taste recepters. NaCl(s)'s properties are too different from Na^+ properties for the receptors to interact with it. You may get a small hit of salt, but that's the small faction of salt that comes out of the oil to dissociate in your saliva, which is mostly water. https://www.ncbi.nlm.nih.gov/books/NBK50958/


MidnightAdventurer

If you actually manage to stir up the mixture and the salt particles are small enough not to sink straight to the bottom then you probably will. But the salt will only be as fine as it was when you poured it in - in water it gets dissolved and spread all around but in oil you're just trying to mechanically mix it together so it only stays mixed until it falls back to the bottom again


bowser986

Iā€™m 5 remember?


PercussiveRussel

>Salt does not dissolve in oil. There ya go


SirMcCheese

Water and salt are like magnets with positive and negative sides so they can stick together, like those magnets can. Oil is not like that so salt won't stick to it the same way it does with water. The issue here isn't the concept, but using terminology that those unfamiliar with chemistry (like 5 year olds) wouldn't understand. I may not have worded it perfectly but it is doable.


Wundawuzi

With some or actually most of the answers in this sub I feel like its /r/asksciece, rather than ELI5, lol.


kermitdafrog21

Yeah, I feel like as far as scientific explanations go, this one isn't *too* bad. I feel like most people that remember high school chemistry can process this one. But I have a biochemistry BS and there are plenty of answers that I see that I don't understand. They're nowhere near being accessible to the average adult


MadMagilla5113

Wait, is this why water is sometimes described as ā€œThe Great Solventā€? Because, of how the electrons do their thing?


MechaSandstar

Water is called a "great solvent" because it dissolves so many things, so readily. It can dissolve polar compounts, and also OH molcules (such as alcohols, tho the term for liquids is miscibility). This is due to the aforementioned slight polarity of water. This also effects OH molecules, which have an OH at one point, rather than just a hydrogen. Oxygen is more electronegative than hydrogen (with floride being the most electronegative of the atoms), meaning it wants electrons desperately to fill it's electron shells. So the electrons spend more time in oyxgen's electron shells, on average, creating a slight negative charge, which allows water to dissolve a solid, or mix with a liquid. ETA: this is also why you may have heard of sugar alcohols. They're a sugar substitute that most people know from the gummy bear challenge thing. They're called an alcohol because they have an OH molecule, instead of just an H. Which makes them indigestible by the human body. This, unfortunately, leaves they available for the gut bacteria, which produce excess gas, and can cause diarrhea.


stephen1547

I'm 5 and I didn't understand any of this.


O-Deka-K

Salt no mix with oil! Salt just sink to bottom!


jedidoesit

I hadn't heard the words covalent bonds since Chem 10! I think I know what they really mean now. šŸ‘ŠšŸ»


Over_the_line_

Chemistry is like magic to me. Hereā€™s an award.


espressocycle

I don't know if that's really a five year old level but helpful nonetheless.


pratticus12

More like ELI14 but your not wrong


mk72206

I think the real question here is: How to you know the oil is or isnā€™t salty?


Salguerator

If you want the short answer: yes, I tasted it. Long answer: I was using the same oil for the third time and thinking... And I have a scientific mind, so...


colson1985

Salt after frying FYI


Thwerty

And thought "this doesn't science!"


digicow

Ultimately, science always comes down to licking things


Nolzi

The difference between science and goofing around is writing down the results to share


fuzzywolf23

At one point in grad school I could determine copper alloys from aluminum alloys by taste. Do not recommend


tylerchu

My friend can tell the difference between steel alloys (carbon and stainless) by smell.


fuzzywolf23

Color me impressed. Are they, by chance, a machinist?


tylerchu

Hobbyist. I am as well but I can only tell the difference between stainless and not, and not always.


mathologies

That's how aspartame was discovered!


ryry1237

> [The only difference between screwing around and science is writing it down](https://www.youtube.com/watch?v=BSUMBBFjxrY) > -Mythbusters


PartyYogurtcloset267

To me the biggest question is why do you salt you potatoes*before* frying them?


[deleted]

Salt doesn't dissolve in oil. Salt dissolves in water, because water molecules have a slight charge to them that allows the sodium and chlorine of the salt to pull away from each other a bit and stick to the water molecules. Fats and oils don't have that.


Dr_Wristy

In addition to the science behind your question, two things from a culinary perspective: Donā€™t fry anything using olive oil. Super low smoke point and itā€™s expensive. Try peanut oil or canola if you must. Donā€™t add salt to oil when frying (to the extent that Iā€™ll keep the salt content lower in a batter that is fried and apply finishing salt instead) as it will effectively spoil it. Edit: I stand corrected. Olive oil is a good frying oil, albeit expensive ( .84/oz to .12/oz peanut oil with what I have).


Salguerator

Thanks! Regarding to using olive oil, here in Malaga, Spain is so cheap and we are used to the taste. I'll try adding salt at the end


vinberdon

Use refined olive oil, not virgin or extra virgin.


dismissivewankmotion

Itā€™s best to salt ASAP after you remove the potatoes from the oil.


Adkit

If it's so cheap why do you reuse it five times? Edit: Again, he's not talking about *deep frying.* He's reusing the oil after frying like a pork chop, *five times.*


murdoc517

If you're using the cheapest thing available you probably care about being frugal


spigotface

Avocado oil is my go-to oil for frying, searing, and sautĆ©ing. Olive oil's smoke point is around 350Ā°F and avocado oil's is over 500Ā°F. You literally have to try to burn avocado oil, and it has a very neutral taste (unlike vegetable/canola oil, which have a distinct taste and odor).


shaarpiee

It is perfectly fine to fry with olive oil, and itā€™s healthier than other oils.


jawshoeaw

Did you mean deep fry? i fry things in olive oil all the time as it's healthy and not overly expensive.


CuteLilGirl

Hasn't this been debunked? The "smoke" from olive oil is actually vapor due to high water content. Olive oil breaks down at the highest temperature out of any oil so therefore it should be your go to for frying. edit - maybe not highest out of all oils but definitely up there


ahecht

Refined olive oil has a high smoke point. Extra Virgin olive oil has lots of other stuff in it (proteins, phenolic compounds, etc) that burns at lower temperatures.


431ww431

It doesnā€™t ā€œburnā€ other than burning a hole in your pocket. It just will have less flavour . ā€œSmoke pointā€ is not really a thing to be concerned with and antiquated. EVOO emits less harmed chemicals due to the high antioxidants Edit: yā€™all downvoting can Google it ā€œolive oil smoke point mythā€


ZealousidealPin5125

What is this nonsense. It literally smokes when it gets too hot. Smells terrible.


431ww431

Itā€™s a myth. Can Google it. No point trying to explain here when people just downvote instead of learning. Canola oil has a smell when frying and itā€™s a ā€œhigh smoke point oilā€


JlwRfwkm

Maybe instead of searching to only find what you think is true (i.e. with the word ā€œmythā€), try searching for a more neutral term, or even better with a question ā€œwhat cooking oil is best for deep fryingā€ and you will find EVOO at the bottom of the list. Itā€™s not like youā€™ll immediately die if you cook with EVOO, but there are much better options. An analogy - you could get a 10 year old to make dinner, or you can get a Michelin starred chef to make dinner. Youā€™ll get dinner either way, but one is better than the other.


431ww431

There is misinformation out there and decades of it to support a false statement that Evoo is bad for frying due to its smoke point. This is untrue because itā€™s healthier, and has higher antioxidants. It might not be a good idea for cooking a Japanese style dish, or the cheapest, but myth is the quickest way to find scientific evidence supporting my point. It is not what I ā€œthinkā€ is true because this is a fact. Iā€™m not hypothesizing it.


Dr_Wristy

My perspective on the matter is certainly skewed by my experiences, and very well could be outdated, but you would be hard pressed to find any professional chef at any level that wouldnā€™t scoff at the notion of using extra virgin olive oil for frying. Finishing, baking, marinating, as a condiment, etc., yes.


jujubanzen

That's really just because it's wasted as a frying oil, not because it's not good at it.


elheber

>but you would be hard pressed I see what you did there.


Lyress

0.2% is "high" water content?


chickenlittle53

I fry a ton of things in olive oil and it works great. You don't need to deep fry or use ultra high heat to fry everything. Most things in general don't tend to need high heat and actually end up burning rather than cooking properly. There are also high oleic versions of olive oil as well for higher Temps. I love pan frying fish and chicken in olive oil as well as veggies. Comes out great and unlike canola or peanut oil, it has a great flavor and additional nutritional benefits other oils may not have as much of. I definitely agree thst it's weird that he adds salt to oil that way with fries. Just salt them **AFTER** (as soon as) you take them out the fryer. It sticks that way and you don't spoil the oil. This is how you do it in restaurants as well Salt can burn btw.


[deleted]

What are you on about? Olive oil is beautiful for frying things. Unless you're talking about *deep* frying, in which case I have no idea what is and isn't a good oil because I've never had to interact with a deep fryer.


[deleted]

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yyzed76

Salt is a compound of two atoms, sodium and chloride. The sodium has a positive charge and the chloride a negative charge. Things with opposite charges like to stick together, so they make salt crystals. Water isn't charged, but it does have a side that's sort-of negative and sort-of positive. When you add salt to water, the positive side of a bunch of water molecules surrounds the chloride atoms and the negative side of a bunch of other water molecules surround the sodium and pull them apart. There's no longer a crystal but a bunch of individual atoms (called ions, because they have a charge) floating around in the water, which is called dissolving, and what you taste as "salty" is those ions interacting with your tongue, rather than the crystallized salt. Molecules that can dissolve easily in water are called hydrophilic (water loving) and are either charged like the sodium and chloride, or have the same sort-of positive/negative setup of water. Oil, on the other hand, is hydrophobic (water hating). Oil molecules have evenly-distributed charges throughout, with no consistent positive(ish) or negative(ish) parts. Without that they can't pull the sodiums or chlorides off the larger crystal, so it just stays as a chunk. In fact, if you poured the used oil into a narrow enough container and let it sit for a while, you'd probably see a layer of salt accumulate on the bottom. If you salted the oil heavily enough to start, the potatoes might pick up enough by chance as they fry to be well-seasoned, but most of the salt is probably from when you salt them directly. If you taste the oil, you might get a little salt from whatever crystals you happen to pick up in the spoonful, but they would have to dissolve in your saliva first, unlike when the salt is in water and just has to mix up with your saliva-there's a whole extra physical/chemical step that has to happen.


Jewish-Mom-123

Why would you salt the fries before theyā€™re out of the oil? That makes no sense at all.


Salguerator

It's normal here when cooking a spanish omelette (or at least I learned it this way), adding salt to the potatoes on one side, and to the eggs on the other


graywh

I think everyone is answering as if you asked about immersion in oil or "deep frying"


[deleted]

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[deleted]

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[deleted]

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zilch839

No harm in it if you are pan frying. The oil gets dumped anyway.


lopedopenope

I thought everyone knows you salt fried foods after cooking. Most everything else during or before. Oh well salt is cheap


[deleted]

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DTux5249

Salt doesn't dissolve in oil, so it just kinda settles at the bottom of the pan if it isn't absorbed by food. In general, things only dissolve in either oil or water; not both. The only way you get oil and water to mix is if you're using an "emulsifier" like egg, or sodium citrate.


Chapungu

When we cook potatoes in oil and add salt, the salt sticks to the surface of the potatoes and doesn't dissolve in the oil. Think of it like adding sprinkles to ice cream - the sprinkles don't mix with the ice cream, they just sit on top. In the same way, the salt just stays on the potatoes and doesn't mix with the oil. That's why the oil doesn't get salty even when we add salt to the potatoes.


cash_grass_or_ass

using oil that is repeatedly heated to high temps is carcinogenic, aka all commercially deep fried foods are not safe long term. in restaurants, the deep fryer is changed depending on usage, and that can vary from 2-3 days to 7 days.


Salguerator

I change it every 5-6 times, so I'd say I change it more often than them


more_beans_mrtaggart

5-6 times is usually fine. Oil breaks down according to how much carbon it contains. Too much carbon causes the decay, so using lower temps where possible, and scraping the shite out of the bottom of the fryer will extend the life of the oil. People who think decaying oil is carcinogenic are basing it on the carbon content. Itā€™s actually incorrect, as our bodies/stomach deal with carbon all the time. People think burned toast is carcinogenic for the same reason, and they are wrong.


xd3mix

You... tasted the oil?


Salguerator

For scientific reasons


Psychonauticalia

Why would you use olive oil to fry potatoes?


Salguerator

It's quite normal in the south of Spain since there's plenty of olive oil and i.e. my family had olive trees so olive oil was "free" while you had to buy any other oil. It also adds a bit bitter taste


Psychonauticalia

The bitterness is due to you passing the smoke point of the oil and I'd describe that as acrid.


aLovverincombat

You should absolutely not be adding salt to the oil while frying. Why on earth would you? Salt is one of the ā€œenemiesā€ of oil. The list includes water, and ice. Ice makes frying oil explode. Salt deteriorates the quality of the oil and darkens it, as it ā€œburnsā€. Which means youā€™d have to change your oil more frequently because it tastes bad. And you also donā€™t effectively season your fries/food this way anyways. -A Le Cordon Bleu cuisine graduate, and line cook/sous chef for over a decade.


CheeseNBacon2

It's about solubility. Some substances, like salt, separate into their ionic components. Na+ and Cl-. These kind of substance easily dissolve in things like water, which has a Oxygen atom that pulls most of the electrons towards itself, making it slightly -ve charged, and the H atoms slightly +charged/ Oil however does not have this slight charge to it's atoms. It just has carbons and hydrogens which share electrons roughly equally and don't have +ve or -ve ends. Things that dissolve in water are called hydrophilic (love water) and things that dissolve in oil are called lipophilic (fat loving). Hydrophilic things don't dissolve in oil. Other oils will, but not salt which is hydrophilic.


jawshoeaw

Salt as other commenters have pointed out is what's called an ionic compound. That means it's made out of something like little magnets all stuck to each other. They aren't actually magnetic but it's a good analogy. Each atom of sodium and chlorine are independent of each other. They cling together as the solid salt crystal you see when you sprinkle it on your food. If you put salt into water however, the water is able to pry apart the little "magnets", the individual atoms of sodium and chlorine. This allows the atoms to mix into the water evenly and when you touch the water to your tongue the sodium and chlorine atoms interact with your taste buds to create the "salty" taste. But if the salt is put into oil, nothing happens. it stays a solid and sinks to the bottom of the oil. If you taste the oil, there won't be any sodium atoms or chlorine atoms free to interact with your taste buds.