Why Does Changing Just One Proton Change an Element?

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WHY IS SODIUM A METAL BUT ARGON IS A GAS?
Electron configuration determines this. Sodium atoms can form metallic bond because the positively charge cation K+ forms an electrostatic attraction with the delocalized electrons from the outer shell. Argon cannot form such bonds because there is no delocalized electron nor cation formed, since the electron structure of the atom is already stable.

CHAPTERS
0:00 Adding or subtracting one proton: drastic change
1:58 The simple answer
3:00 Soylent is best tasting
4:07 Why are elements not classified by electrons?
5:35 Number of protons can change, but not in chemistry
6:07 Why proton count is used to classify elements
6:50 Why are there orbitals and electron shells in atoms?
9:01 How chemistry works: all about energy
12:24 Why aren't all elements Noble elements?

SUMMARY
Why does changing just one proton in the nucleus of an atom make a different element? How can a single proton make such a huge difference in an element’s properties?

The simple answer is: The number of protons determines the number of electrons the atom needs in order to be neutral. The number and configuration of the electrons of an atom determines its chemical properties. So since the number of electrons is determined by the number of protons, changing even just proton will change an element's chemical properties.

If so, why don’t we classify elements based on their number of electrons instead of protons? The reason is because electron numbers for most atoms, can be changed by taking on or giving away electrons to and from other atoms. This is the basis of chemistry. But the change in electrons does not affect the element's essential nature. It still retains its atomic properties.

But the number of protons never changes for most elements. It remains the same because protons cannot be exchanged with other atoms like electrons can in chemical reactions. So the proton count of an element does not change in chemical reactions. This proton number, in turn, determines the number of electrons the atom needs to be neutral. And that in turn, determines the behavior of the atom when it interacts with other atoms chemically, i.e., the bonds it can form. And this determines both its chemical and physical properties.

The proton number determines the propensity of that element to keep, give away, or share its outermost electrons with other atoms.

Electrons in the outermost shell of an atom determine its chemical properties. Why are there different electron shells? Atoms and molecules tend to favor the state with the lowest potential energy, because of the second law of thermodynamics - the law of entropy.

Solving the Schrodinger equation shows how the energies of the electrons in any given atom will be distributed in its ground state. When we solve it, we find that electrons are distributed in orbitals and shells around the nucleus.

An orbital can contain only a maximum two electrons due to the Pauli exclusion principle. The Schrodinger equation shows that as the number of electrons increases in an atom, they occupy different energy levels or shells around its nucleus. These shells can only accommodate a maximum of a fixed number of electrons. These numbers are 2, 10, 18, 36, 54, 86.

So for the few elements that have exactly these protons numbers, they will have the precise number of electrons that make their atomic structure energetically stable. Consequently, they will not have the propensity to take on or lose any of their electrons to other atoms. These are the Noble elements.

Chemistry works by elements trading electrons to form neutrally charged systems that are more energetically favorable, than the elements on their own. Proton number is key because it is the main factor in determining what number of electrons an element would prefer. It boils down to energy and charge conservation.
#protons
#elements
One could ask, why aren’t all elements noble elements. Why didn’t nature make all elements stable? The reason is that elements were formed in fusion reactions within the cores of stars or star processes. The fusion process results in nuclei with all kinds of different numbers of protons, not just the noble elements. Fusion is a nuclear process that just makes stable nucle, not a chemical process that optimizes electron shell stability.

[crazyengineer]

"Protons give atoms their identity. Electrons give them personality"

[ImmortalLemon]

I think what I like most about your channel is that you assume we know the basic concepts of what you’re talking about, so you only mention them to give context and then move on to the actual information. It’s so nice to hear from a science educator that knows the level of knowledge their audience has

[kerrynewman]

Absolutely great video. At 64 years old this engineer never gets tired of learning new science.

[bhm]

Brilliantly explained. However, this only partially answers the question. The "why" goes much deeper for me, where lies the code that dictates the behavior of the element when changing its configuration? Why is it what it is? I guess we have to accept the old saying: because it is what it is. At least for now.

Let's suppose there is an island of stability for superheavy elements. Could we predict their behavior, or would we need to wait for nature to show us how they behave? We don't even know if this island exists, let alone make such predictions. To me, this just demonstrates how precarious our illusory knowledge of everything is.

Don't get me wrong, we have come a long way and made sensational discoveries, but our progress is small compared to the grand scheme of the universe. At least, that's how it seems to me, or maybe my "whys" aren't good questions. I hope I have been clear. Excellent content, as always.

[dermotthompson]

Has nobody seen the classic old movie Soylent Green???

[jamesedward]

Closing in on a million subscribers. Arvin deserves about 100X that many. Every time I think the internet is a pox on humanity, I remind myself that there are individuals like him making videos like these. Whether you're a serious student of science and math struggling to understand a concept or just someone who is a hobbyist/casually curious about these topics Arvin is your guy. I know it's a cliche now but this youtube channel "is a treasure".

[north]

One of the best videos Arvin has produced. Helped by the background, irrelevant, music being less obtrusive. Thank you.

[TaxEvasin]

I am learning about this stuff for the first time as a grown, matured adult.

This is seriously making me ponder about my existence and what or who put it all together. This is just incredible, I've not felt this sense of awe in a very very very long time.

[vitovittucci]

When I was a young chemistry student there was a simple rule to predict the tendency of an atom to acquire or give electrons : the rule of the "8 electrons outer shell ". Every element tends to complete this shell of 8 electrons: a) acquiring the missing electrons . b) giving the exceeding electrons. c) sharing electons with other atoms. Later I understood that at the basis for this there were reasons concerning energy and stabiity. However this rule works pretty well and I always wandered why it was sufficient considering just 8 electons instead of the entire electronic configuration.

[Bp]

I love this question, but i love that a video on it was made. We need more videos with these types of questions answered. There are so many seemingly simple questions with profound answers that many of us wish were answered. Thank you!

[NCrPhbA]

OK, but you didn't explain what you said you would. You explained what causes them to react; that's highschool chemistry.

Why exactly is potassium a soft metal and argon a gas... Why do they have such drastically different forms? Is it's propensity to bond with itself in clumps? How? Crystals? Cohesion? Electromagnetism? Nuclear forces? Why the difference there. Why does light interact with one not the other?

Reactions due to valence shells is easy to understand and describe, mate...

[ryanbaker]

Fabulously explained, Arvin! I wish I had the understanding of QM and QFT that I have now back in high school, lol. This video also explains why I prefer to sit in the recliner watching QM videos than mowing 4 acres of yard...I'm in my ideal, low energy state!

[shahrulandean]

Chanced upon this video. I love how clear his explanations are, as he explored in depth, step by step, to address the subject matter. Love watching clean presentations like this. Subbed! Gonna binge watch more!

[_j_j]

"Crikey mate! I can't bloody well tell if that flamin' cat is alive or dead, struth" - Australian Schrodinger, probably. 😁

[louieuow]

Australia needs more Noble Prize winners, we will take Erwin as one of ours!

[windfoil]

Well explained. I've seen and read about the periodic table and sharing electrons but not the proton distinction before. This was pretty easy to follow and remember. Thanks.

[vivekpatel]

Hey Avi, just came here to thank you for your standard model video.. I just defended my thesis and now a PhD. Thank you for making it easy to understand, it was very helpful.

[yoface]

Thank you so much for the video ash, I remember in high school and college the teachers would always list off or tell you the “what” and “how” for stem topics but when asked, frustratingly never would answer the _why_ things or processes exist the way they exist.

And now onto the next video hopefully of you explaining the _why_ of the specific number for each electron shell, you explained the first orbital shell of 2 but none of the other ones.

[MercuriusORG]

Hi. Great episode.
One thing I spotted is that Erwin Schrodinger was not Australian, but Austrian.

[oTiSm]

Hey Arvin,

I wish you had also mentioned the “cloud model” of the atom in your video because this solar system model is now outdated and I would have loved to accurately imagine what the atoms look like and what electron position means from the cloud model perspective.

Thanks for your amazing videos!