The Stuff You Should Know Doin’ Science Playlist: Legs! Legs! Legs! (The Periodic Table)

19 Jun 2026 · 47 min · 20 chapters

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In short

The periodic table—how it evolved from early ideas about elements to the modern layout, and what rows, columns, and blocks mean (periods/shells, groups/valence electrons, s/p/d/f blocks/quantum positions). It also covers isotopes, ions, lab-created elements, and why the table still has gaps and alternative designs.

Guests

Josh, Chuck, and Jerry (Stuff You Should Know hosts). They thank Livia for helping with the episode.

Key claims

Dalton’s atomic theory (1803/1804) and atomic weights preceded periodic organization; Mendeleev (1869) arranged elements by similarity and left gaps that were later filled; the modern table is ordered by atomic number (protons), and chemistry is driven mainly by valence electrons in the outer shell; quantum mechanics replaces Bohr’s simple “planet” orbits with electron energy “waves,” shaping s/p/d/f blocks.

Notable examples

Oxygen weighing 1.5 grams per liter; lithium/neon electron-shell counts; fluorine’s reactivity from an almost-full valence shell; carbon’s isotope-weighted atomic mass (12.011); technetium as element 43 (first lab-created); Einsteinium (99) from Marshall Islands tests; naming rules (e.g., Nihonium, Oganesson); “Stardust” rejected for naming.

Written by AI. May contain mistakes. Listen to the episode to check what was said.

Chapters

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The Periodic Table Journey

3:07 to 6:04

Discussion on the history and development of the periodic table.

“This is the Only Time I Hate My Job edition.”

Early Theories of Matter

6:04 to 8:11

Exploration of early scientific theories about elements and atomic theory.

“I know I can get some of this at the beginning.”

Mendeleev and the Periodic Table

8:11 to 13:44

In-depth discussion about Mendeleev's contributions to the periodic table.

“Like, they were doing all the stuff that a high school chemistry teacher does to demonstrate chemistry.”

How to Read the Periodic Table

13:44 to 14:01

Explanation of how to interpret the periodic table's layout and elements.

“That's why if you look, and we should probably say the way you read the periodic table is from left to right and top to bottom, right?”

Introduction to Protons and Electrons

14:01 to 14:15

Learn the basic structure of atoms, focusing on protons and electrons.

“And because it has one proton in its stable form, it has one electron.”

Conclusion and Transition

15:31 to 15:55

Conclusion of the setup material and transition to the next segment.

“With Trashy, you can donate your clothes, reduce waste, and earn cash rewards.”

Conclusion and Transition

15:59 to 16:13

Conclusion of the setup material and transition to the next segment.

“Made-up facts, technology thinking for you, Startpage is the private search engine that still finds what you need without the noise.”

Understanding Atomic Numbers

16:23 to 17:53

Discover how atomic numbers define the uniqueness of elements.

“All right, so the modern periodic table, I think, where was Mendeleev?”

Elements and Their Arrangement

17:54 to 19:20

Learn how elements are arranged in periods and groups in the periodic table.

“If you add a proton or take away a proton, you got a totally different element, which is why you can order them by their atomic number.”

Electron Shells and Their Importance

19:21 to 20:28

Understand electron shells and their role in atomic structure.

“all the elements on each row have the same number of electron shells.”
Show all 20 chapters

Reactivity of Elements

20:29 to 22:40

Explore how the arrangement of electrons affects element reactivity.

“One shell, then the second shell, then the third shell, then the fourth shell.”

The Significance of the Periodic Table

22:41 to 27:34

Learn about the practical applications and importance of the periodic table in chemistry.

“The groups are what we're going to talk about next, and those are the columns.”

Periodic Table as a Map

27:35 to 28:00

Understand the periodic table's analogy to a map for predicting element behavior.

“And I saw it described by a chemist really well.”

Understanding the Periodic Table

28:00 to 37:38

Learn how the periodic table is structured and what it reveals about elements.

“To a chemist, a periodic table looks like a map to us.”

Understanding the Periodic Table

37:39 to 39:28

Learn how the periodic table is structured and what it reveals about elements.

“And when we come back, we're going to tell you about how things got very interesting in terms of the periodic table in the 1930s right after this.”

Advancements in Element Discovery

39:33 to 42:00

Explore the creation of new elements and the historical context of their discovery.

“Startpage is the private search engine that helps keep what you look up online from becoming a price tag.”

The Naming of Elements

42:00 to 45:07

Learn how elements are named and the significance behind their names.

“When they started doing the nuclear tests out on the Marshall Islands in the 50s, they would send planes out into these explosions with filters on them to scoop up unusual atoms and discover potentially elements.”

The Structure of the Periodic Table

45:07 to 47:18

Explore the periodic table's structure and the rationale for its design.

“You needn't only look at the very first one, hydrogen, at the far left of the table.”

Alternative Periodic Table Designs

47:18 to 50:56

Discover various artistic and scientific interpretations of the periodic table.

“There are some, and it's kind of fun to look some of these up if you want to see some kind of cool, at the very least, just aesthetic examples.”

Unique Properties of Elements

50:56 to 54:28

Understand how relativistic effects influence the properties of elements like gold.

“Well, since I said Murphy's Law and Chuck laughed because he got the joke, you may not have him.”
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Transcript

Automatic transcript. May contain errors.

0:00Josh Clark:This is an iHeart Podcast. Guaranteed human. Mom, can I have Lingo Kids?

0:06Chuck Bryant:Dad, Lingo Kids, please!

0:08Josh Clark:When did we become the Lingo Kids house? No idea. Last week it was dinosaurs. This week it's... Lingo Kids! Why Lingo Kids? Because it's the best thing ever. We can play games. With astronauts. Wild animals. And superheroes.

0:20Chuck Bryant:With more than 4 ,000 interactive games, songs, and shows, Lingo Kids is the number one entertainment platform for young kids. So, no dinosaurs? and dinosaurs. Mango kids. Everything kids love. Download it for free. You know that pile of clothes you've been meaning to deal with? Yeah, same. That's why I love Trashy. It's the easiest way to clean out your closet, send your clothes somewhere better, and actually get rewarded for it. No more letting things sit around or wondering what to do with them. You just fill up a take-back bag with clothes you don't wear anymore. Send it in, and Trashy takes care of the rest.

0:58Chuck Bryant:keeping it out of landfills and giving it a second life. It's such a simple way to feel good about clearing space and doing something better for the planet. And here's the best part. You earn cash rewards back for every bag you send, which makes it even easier to stay consistent. You can check it out at Trashy.io. Plus, with Trashy Unlimited, you can get unlimited bags for just$48 your first year. An easy at-home clean-out system, so you can stay on top of it all year long. Clean out, donate, earn rewards. Head to Trashy.io to get started today. Do you want to find a stress-free way to buy your next car?

1:38Chuck Bryant:Start at CarMax and shop your way. If you want to browse with confidence, get pre-qualified online with no impact on your credit score and shop cars within your budget, from luxury cars to family rides. CarMax has options for almost every price range, including more than 25 ,000 cars priced under$25 ,000. So, hey, want to get started? Just head to CarMax.com for details and get pre-qualified today. Want to drive? CarMax. Here we are, friends, the last episode of our Doin' Science playlist. It's been quite a ride, hasn't it? If you're super bummed about it ending, you can just start all over again.

2:19Chuck Bryant:This episode on the periodic table that we released just a couple years ago became one of my favorites because I had to give myself a crash course in chemistry and I learned a ton of stuff that I never knew and probably never would have learned if we hadn't taken this one on. As you will hear, I got pretty jazzed about it. I hope this episode gets you jazzed about it too. And thanks a lot for spending some of your time with us listening to our Do in Science playlist. We'll be back in September with another one. Until then, keep testing your predictions.

2:52Josh Clark:Welcome to Stuff You Should Know, a production of iHeartRadio.

3:02Chuck Bryant:Hey, and welcome to the podcast. I'm Josh, and there's Chuck, and Jerry's here too. And this is the We'll Get Through It edition of Stuff You Should Know about the periodic table.

3:14Josh Clark:Uh-huh. I have other names for it.

3:17Chuck Bryant:I'll bet you do. Can you say any of them?

3:20Josh Clark:This is the Only Time I Hate My Job edition. This is the Now We Can Stop Talking About the Sun episode.

3:30Chuck Bryant:Maybe.

3:31Josh Clark:Edition.

3:32Chuck Bryant:Uh-huh.

3:34Josh Clark:And this is the My God, Why Do We Ever Do Episodes on Chemistry edition? I failed chemistry. It's the only thing I've ever failed was chemistry.

3:42Chuck Bryant:I don't think I even ever took chemistry, to tell you the truth.

3:45Josh Clark:Hey, you didn't fail it.

3:47Chuck Bryant:Right. Can't fail if you don't try. That's my motto. Here's what I figured out about this, like driving myself mad trying to learn this stuff and understand it. There is a lot of people out there who have written articles and explainers on the stuff that we're going to talk about who literally don't know what they're talking about. And yet they're presenting their information like they do. and it's wrong and you can't understand it. Or in cases where you can understand it, it still doesn't fully answer the question. There's a lot of stuff out there like that on this, especially as it gets more and more like arcane, right?

4:30Chuck Bryant:There's a whole group of people out there, chemists, molecular chemists, physicists, who understand this, but you can put them all together and they can't coherently explain any of it to anybody else. They can just talk to one another like this. Where we are, where us and everybody listening to this episode right now is stuck in the middle. We know enough that we can notice when somebody is wrong or not correct or doesn't know what they're talking about. But we don't know enough to understand what the actual scientists are saying and then come back and explain it. So, first of all, Breton cap off to Livia for helping us with this one.

5:10Josh Clark:Boy, Livia should get a bonus for this one, quite frankly.

5:13Chuck Bryant:For sure. And then second, we might have to edit that out. We'll have to check the budget. Secondly, we're smart enough to get all this across. We are. But we're also transparent enough to admit when we're like, we don't understand this part.

5:30Josh Clark:Yeah. I mean, there's a few parts I still don't get. I imagine the good news is I imagine that maybe about 20 % of our listenership is even hearing this right now.

5:41Chuck Bryant:I hope more than that because it's really interesting stuff.

5:45Josh Clark:Would you click on something called How the Periodic Table Works?

5:48Chuck Bryant:Well, we're going to have to come up with something else. I think we'll call this one Legs, Legs, Legs.

5:56Josh Clark:Colon, tiny lettering, periodic table.

5:58Chuck Bryant:Exactly.

6:00Josh Clark:The sex episode.

6:02Chuck Bryant:Right. We'll see. We'll trick them into listening to it.

6:07Josh Clark:All right. I know I can get some of this at the beginning. So if you'll allow me to talk about one of the only parts I understand. Sure. All right, great. I'll kick it off because we have to set the stage sort of for pre-periodic table construction, which is to say that early, I'm sorry, late in the 18th century, we were working from, scientists working from the Aristotelian, Aristotelian, yeah, that's to say Aristotle's system, which is, which we've talked about some recently, which is, hey, we got four elements, fire, earth, water, and air. And then after that, science became a little more nuanced.

6:47Josh Clark:And they're like, hey, actually, we think there are more things out there, more building blocks. Yeah. And maybe we can distinguish them from one another and categorize them, maybe based on their mass. And this was sort of the scene when in 1804, oddly, an English schoolteacher who was also a researcher named John Dalton said, all right, things are made up of smaller things. Maybe these, which is not new, like for, you know, ancient cultures were even talking about things being up of smaller things.

7:20Chuck Bryant:Yeah, we talked about democritus in that episode about things we believe before the scientific method.

7:25Josh Clark:Totally. That's exactly where it was. But he said things are made up maybe of like these little tiny indestructible, indivisible atoms. He got a lot of that wrong. But one thing he got right was the idea that no two elements that we know about so far, which were not very many at all at that point, can have an identical mass. And all the atoms of that element have the same mass, which also wasn't quite right. But at the time, it was right.

7:54Chuck Bryant:Yeah, because you got to give it up to these guys. When we're, like, analyzing elements and atoms and stuff today, we're using, like, spectrometry and particle accelerators and doing all sorts of amazing stuff. These guys are, like, burning things. This is 1804. Boiling them in acid. Yeah. Like, they were doing all the stuff that a high school chemistry teacher does to demonstrate chemistry. That's what they were doing to actually isolate elements and, like, weigh them. They were weighing things like oxygen. Like they figured out that if you take a liter of oxygen, you will find that it weighs 1.5 grams.

8:30Chuck Bryant:No matter where in the world you weigh it, it's going to weigh 1.5 grams. Like that's what these people are doing. Can you capture a liter of oxygen? I can't. I can't. So I mean like what they were doing was the hardcore like bloody like roll up your sleeves kind of chemistry. Yeah. Like apparently it was like one of the biggest scientific pushes of the 19th century was identifying elements. And John Dalton was the first to say, hey, some of these I think we can kind of like try to organize them a little bit. And Dalton didn't discover any elements from what I understand. He was just the first one to come up with atomic theory in the modern age and try to start ordering them based on atomic weight.

9:16Josh Clark:Yeah, exactly. It wasn't quite the periodic table yet, but it was a precursor for sure. And his very first version in 1803 only had the five elements that we knew about at the time, hydrogen, oxygen, nitrogen, carbon, and sulfur. Nitrogen was known as, I think we said this in the other episode, the azote? Or is it azote?

9:37Chuck Bryant:I guess.

9:38Josh Clark:Okay. A-Z-O-T-E. His second list, just five years later, was up to 20 elements. And then 24 years later, by 1827, that list was up to 36. And as science was progressing, they started noticing patterns. And they started noticing sort of intervals where things would repeat themselves such that all of a sudden a German chemist named Johann Wolfgang in 1829 said, Well, wait a minute. We're noticing these patterns. And some of these things are the same. Like if you look at lithium, sodium, potassium, they have very similar properties. And we might can group those together. And those three in the modern periodic table are grouped together in the same column.

10:24Josh Clark:So he was right on the money as far as that idea.

Read the full transcript

10:27Chuck Bryant:Yeah. And I mean, we as humans are obsessed with finding patterns and things. And like discovering a latent pattern in nature. I mean, there's few things more exciting than that. So these guys were looking for patterns even in places where they didn't necessarily exist, maybe maneuvering things where they should or shouldn't be. Some people took some cracks at it to try to kind of organize these elements by pattern, but they ran into some problems. One was the chemistry wasn't as exact as it needed to be to really organize stuff. There were elements that hadn't been discovered yet, so there were big missing chunks, but they didn't necessarily know there were big missing chunks.

11:06Chuck Bryant:But they were on the right track, that you could order these things one way or another. And when you did, they would start showing patterns. Periodicity. Periodic table means that there are periods or patterns that repeat themselves depending on how you organize these elements.

11:25Josh Clark:Yeah. And the modern periodic table that we know and loathe, sorry, I loathe, that thing that they pull down in science class that, you know, teenagers just blankly stare at, not knowing what the heck they're looking at. But it's pretty. Sure, if you say so. We owe that to a Russian chemist named Dmitry Mendelev. And Mendelev in 1869 was working on the very first Russian language organic chemistry textbook in 1869 and said, you know what, we have 63 elements at this point. I think we can organize these. And he did so. He arranged things in like columns. He had to reorder some things from the previous order.

12:18Josh Clark:So he's like, maybe we shouldn't organize just by atomic mass. Maybe we should order them into these similarities and how they behave. And the big, big thing that Mendeleev landed on was leaving gaps where he saw gaps. And instead of just, you know, buttoning it up and making it look a certain way, he said, I'm going to leave a gap here. And this is actually what kind of proved his worth in the fact that he was really on the right track. Because in the 15 years following him leaving those gaps, three elements were discovered that fit those very gaps that he had left perfectly, like a little puzzle piece.

12:55Chuck Bryant:It's like the molecular chemistry version of Babe Ruth calling a shot. Yeah, basically. Essentially. So, like, when it turned out in the next 15 years, they found those elements that did not only fill those spots, but they had properties that Mendeleev predicted they would. Like he was like they were like, you did really good guy. He also predicted some other ones that didn't come true. But everybody was just like, whatever, it's fine. So that was like the model that everybody used from that point on. And it's the classic model that we see today where it's kind of like a castle with turrets on either side.

13:30Chuck Bryant:And, you know, the brick in the middle. And then there's like a couple of rows below that are remote if you squint hard enough.

13:38Josh Clark:Yeah.

13:38Chuck Bryant:That's Mendeleev who came up with that whole thing. And the way that they're arranged is not by atomic mass, but by atomic number. That's why if you look, and we should probably say the way you read the periodic table is from left to right and top to bottom, right? So the whole thing starts in the top left with number one, hydrogen. And the reason it's number one is because it has one proton. That's right. It has one proton, Chuck. And because it has one proton in its stable form, it has one electron. And all that's going to be important in a minute.

14:09Josh Clark:That's right. I mean, should we go ahead and take a break? I feel like that was kind of good setup material. Sure. All right. We'll take a break and we'll be right back with more things to enlighten you and numb you.

14:35Josh Clark:With my mom and dad living in Orange County, when we bring my five and seven-year-old to visit, we are sometimes in for a two-hour drive that could feel like 10.

14:43Chuck Bryant:Oh, as an avid camper, I know all about this. We'll pack up the RV and know this is either going to be the trip of a lifetime or a complete disaster. Which is why we load up the iPads with Lingo Kids before we even pull out of the driveway. It's what dreams are made of. Lingo Kids keeps kids engaged and quiet with over 4 ,000 interactive games, songs, and shows that kids simply cannot get enough of. You can pack whatever you think you'll need, but Lingo Kids is the only entertainment you'll need for a stress-free car ride. Or really, any ride. Plane, train, hovercraft, whatever. Download Lingo Kids for free today.

15:18Chuck Bryant:Or unlock even more amazing content with Lingo Kids Plus. Choose the yearly plan and save up to 60%. Search Lingo Kids in the App Store or Google Play. Lingo Kids.

15:28Josh Clark:Everything kids love.

15:31Chuck Bryant:Ready to finally clean out your closet? With Trashy, you can donate your clothes, reduce waste, and earn cash rewards. All in one simple step. Just fill a take-back bag, send it in, and get rewards cash back for every bag. And now, with Trashy Unlimited, you get unlimited bags for just$48 your first year. Clean out, donate, earn rewards. Visit Trashy.io to get started. AI is taking over the internet. Made-up facts, technology thinking for you, Startpage is the private search engine that still finds what you need without the noise. Try Startpage at Startpage.com. That's Startpage.com.

16:25Josh Clark:All right, so the modern periodic table, I think, where was Mendeleev? He had 63 on his first. Yeah, 63 known elements at the time on his first stab. The modern periodic table right now stands at 118. And I think they've already said they think possibly maybe one day it may top out at 173. We'll see. We'll see. But that's sort of, you know, the thinking, the logic. But right now we're at 118 elements that we know about. It includes on the chart the name of the element. They're usually a one - or two-letter symbol, which is almost always short for the name. But in a case of gold, like when you see AU for gold and you're like, what the heck is that all about?

17:14Josh Clark:That just means it's based on the original Latin for gold, Aurum. And they are placed, like you said before the break, in order of their atomic number, which represents the protons in each atom. And that is what makes that each element unique over those seven rows, aka periods, and 18 numbered columns, aka groups. Yeah.

17:39Chuck Bryant:So the rows across horizontally, those are the periods. And like you said, it's really important to remember, if you take a proton and add it to an element, you don't have like a variation on the element. You have an entirely new element. Everything else you can mess around with fudge, mess with the neutrons, mess with the electrons. If you add a proton or take away a proton, you got a totally different element, which is why you can order them by their atomic number. Number one with hydrogen, number two, helium, which has two protons, and so on and so forth. When you see that little number in the top left of the square for that element, that's how many protons it has.

18:16Chuck Bryant:But again, as we'll see, if we're talking about on the periodic table, stable atoms, that means that they don't have an electric charge. They're neutral. And that means that they have an even number of protons and electrons. Protons are positively charged. Electrons are negatively charged. And if you have one and one, they cancel each other out. Two and two, they cancel each other out. Or at the very least, they make the electric charge neutral.

18:45Josh Clark:All right. So if you're looking, if you brought up a picture by now of the periodic table because you really want to follow along. Yeah, that's a good idea. God bless you for doing such a thing. And secondly, you might say, well, wait a minute, Chuck. What's that thing underneath everything? We'll get to this in a minute, but those 14 short columns underneath is called the F block. And those are the seventh and eighth periods, aka rows, that are detached. And those are unnumbered rows, whereas the other rows are numbered through 18. So put a pin in the F block. All elements within a period, and again, that is the row if you're looking horizontal, all the elements on each row have the same number of electron shells.

19:30Josh Clark:And when you think about that in your mind's eye, you're probably picturing how we think of that in our mind's eye because of chemistry class and science class, which is, you know, a circle around an atom's nucleus that holds electrons. Right.

19:45Chuck Bryant:Like an orbit. That's Niels Bohr's contribution, although he made plenty of contributions. But the whole idea that we have of the atom being consisting of like a nucleus that's kind of like the sun and electrons orbiting around it like planets, that's thanks to Niels Bohr. And the actual orbit, let's say you have just one circle around the nucleus, that's a shell. It's one shell. Add another one, that's the second shell. Add another one, that's the third shell. And they actually fill up in order. So when you follow along across the rows, the horizontal rows called periods on the periodic table, all of those in that row have the same number of shells.

20:29Chuck Bryant:One shell, then the second shell, then the third shell, then the fourth shell. And as you go down, each row has all the shells that the ones above it had, and now they've added another shell because their other shells are full of electrons.

20:44Josh Clark:Right. So if you look at the periodic table, get out your little picture, and you look at that first row or period, That means it just has one shell capable of holding up to two electrons. And so that's why there are only two elements there. Hydrogen usually has one electron and helium, which normally has two. And then you go down from there, the second and third shells can hold up to eight electrons. So those second and third rows are each going to have eight elements and so on. For the fourth and fifth, it's 18. The sixth and seventh hold 32. And so there are 32 elements on the sixth and seventh rows.

21:24Chuck Bryant:Just to demonstrate a little further. So helium has two electrons in that one shell. Helium's full. The first element on the next row that has a second shell, that's lithium. Lithium has two electrons in its first shell. That's full. But it has an extra electron. So now it's added another shell, the second shell, to house that first electron. and you go all the way down to the very end of that row, that lithium starts, and you find neon. Neon has 10. Its first shell of two is full of electrons. Its second shell that can hold up to eight is full, so it has 10 total electrons. This is what the periods are showing us, the number of shells, and then eventually in a second we'll know the number of electrons that can fill those shells.

22:08Josh Clark:That's right, and the periods of the rows. We're going to say that a thousand times, groups or columns, periods or rows, because if there's one takeaway from this whole thing, you can at least look smart. And when you walk into a room with a periodic table chart and say, and someone says, what are those rows and columns? And you can say, do you mean groups and periods?

22:27Chuck Bryant:Yeah. And then really quickly after that, look at your watch and be like, look at the time. I'm late. And run out of the room so that there's no follow up questions.

22:33Josh Clark:Yeah. And make a U-shaped hole in the wall. Not the letter U, but a Y-O-U shaped.

22:39Chuck Bryant:Yeah. Nice. Did that come through? Sure. It did once you spelled it.

22:44Josh Clark:The groups are what we're going to talk about next, and those are the columns. And this is where Mendeleev realized these patterns were coming into play. And once, you know, subatomic theory came about and we started being able to drill down further and further, we started to be able to get way more specific.

23:03Chuck Bryant:Yeah.

23:03Josh Clark:So these patterns and these rhythms on the columns are based on the number of valence electrons for each element, which means how many electrons you would normally find in that outermost shell.

23:15Chuck Bryant:Yeah, and the outermost shell is important, Chuck, because that's where all the action happens. That's when atoms bond together to make new molecules. That's where the attraction or repulsion happens. Like that is the that's the the active shell. All the other shells are full. And when a shell is full, it's basically content. It just wants to sit there. It wants to be left alone. But if that outermost shell isn't full, then it's ready for some action. It's got its leather jacket on. It's got its dice in its pocket, maybe a switchblade. And it's looking for trouble. Yeah. So more than I think even rows, like all of the elements that are in a row, remember horizontal across a period, they're related because they all have the same shell the same number of shells one two three four and so on the groups up and down the columns they're more related really because they have the same number of electrons in that outermost shell they can have a bunch of different numbers of shells like for example i think um fluorine can have five shells but only one electron in that that outermost shell.

24:23Chuck Bryant:Or it could have one shell and just have one electron in that outermost shell, like a hydrogen. And they're more related because they'll react to other things more than they would if they had different numbers of electrons.

24:38Josh Clark:Yeah, we can add something to something you should remember, because this will make you look even one step smarter before you run out of the room through the wall, just say, oh, yeah, you know, it's organized into periods and groups and the periods of the rows and the groups of the columns. And if you ask me, the columns, aka groups, that's really where it's at.

24:59Chuck Bryant:They're more related.

25:00Josh Clark:They're more related. And then you run through the wall. Right.

25:04Chuck Bryant:So let me give you an example here, okay?

25:06Josh Clark:All right. This is if you want to really, really, really be smart. Remember this.

25:10Chuck Bryant:Right. If you have your periodic table out, really, honestly, it will make this whole thing so much easier. But if you look all the way down to the second group from the right that starts with fluorine, if you look at fluorine, it has, I think, nine electrons. And it's in period two. So we know that it has two shells. So we know that it has two electrons in its first shell. So it must have seven electrons in its extra shell, or second shell. And since we know that the second shell can hold eight, there's one little irritating gap, and it wants to fill it. So fluorine is super duper reactive. On the other hand, you've got things like potassium.

25:52Chuck Bryant:It has only one electron in its hourmost shell. And it wants to actually get rid of that electron. Because I think I said earlier, when a shell is full, the atom is content and happy. It doesn't want to do anything with anybody. If it just has one leftover, like one hole or one electron, it either wants to get rid of that one electron so that it can lose that shell and go down to the next shell, which is full, or it can fill its shell like fluorine wants to with an extra electron. Either way, they're super reactive. And it all happens in that outermost shell, the valence shell. And that's why that's where all the action happens.

26:28Josh Clark:Yeah. And you know what something we haven't even said that I think is important that dawned on me? What? Is the periodic table isn't just a like, let's just do this thing so we can group them together. A periodic table, the periodic table is made and it's organized this way. So chemists and people that really know what they're doing can look at a poster on a wall at any of those squares and know because of where it is on the row, where it is on the column, what color it is, and what block it is. And we'll get to those things in a minute. And they can know a lot of very specific things just because of where it sits and what it looks like and what color it is.

27:11Chuck Bryant:Yeah, they can tell you whether it's going to blow up in water. Exactly. Like, I guess, apparently, sodium, pure sodium does. They can tell you if it's shiny. there's all of this has to do just almost entirely with the number of electrons it has in its outermost shell all that stuff that's the evolution of the periodic table people notice properties physical properties they noticed appearance stuff like that and then as they learned more and more about the atom they figured out why why in the atom those properties existed and they were able to classify those things together in the periodic table so like you said a chemist today can look at that and be like, oh, that's going to be a shiny metal that'll explode in your hand if you look at it wrong, because it's in this group of elements, right?

27:58Chuck Bryant:And I saw it described by a chemist really well. To a chemist, a periodic table looks like a map to us. If you look at a map of the United States, you know that if you are looking at someplace in the north, it's going to be colder there than, say, somewhere in the south. You don't know exactly what the temperature is or anything like that necessarily, but you know generally based on this map, it's a map to the elements.

28:24Josh Clark:Yeah. And it also might, you know, you might think if you're looking at a map of the South, like that's where people are more like this. And in the Midwest, people may be, you know, it tells you a map tells you a lot more than just like what the weather's like.

28:38Chuck Bryant:Yeah.

28:38Josh Clark:Just like a periodic table. So if a scientist, if a chemist looks at silicon, I look at it and I see a capital S lowercase i the word silicon the number 14 in the left hand corner and that it's yellow a chemist looks at it and says well I see it's in between on the row aluminum and phosphorus and in the in the column it's below carbon and above germanium and I see its number is 14 and it's yellow which means it's a metalloid So I can tell you like these 12 things about silicon just because of where it sits on that map. Yes. It's pretty amazing. I just I don't get it, but it's amazing.

29:19Chuck Bryant:Right. I was I was just going to say we're not going to explain what those 14 things are because they're the kind of things you have to go to graduate school in chemistry to truly understand. It's OK that we don't understand it. All you have to take away from this and all we're trying to get across is that trained chemists can look at the periodic table and realize a lot about whatever element they're looking at and figure out how to mix it with other elements to do amazing things. Or if you put together these two things, this is probably the reaction that you're going to have.

29:51Josh Clark:Yeah. And it's also for someone like us, it can get really confusing because when you look at different periodic tables, one thing you'll notice is that the colors may be different. Like there is no, unless I'm wrong, there isn't one completely settled. This is the only way to do it periodic table. Oh, no. As far as a lot of it goes. But like, you know, depending on who you are and how you want to organize a periodic table that you use, those colors may mean different things. So it can get really, really confusing.

30:21Chuck Bryant:Oh, yeah.

30:21Josh Clark:When it comes to that stuff.

30:23Chuck Bryant:For sure. And usually there is like a key or a legend on the periodic table that says this is what these colors mean. But if you take away the colors, the layout of them across and down, if you look at a periodic table, it's generally going to be the same. For any periodic table that looks even roughly like what you're looking at, it's the colors that really kind of change things up. But more and more, as we've learned more about the atom starting in the early 20th century onward, and quantum mechanics kind of became a thing, that got incorporated into the periodic table as well. And that is where we get to essentially the third way that the whole thing's organized, which is by blocks, subshells, S, P, D, and F.

31:12Chuck Bryant:and so the number of shells that an element has, that's its period across, the number of electrons in its outermost shell, that's its group, the blocks describe where that outermost electron is. And if you'll allow me for a second to just kind of take a little divergence here, It helps you understand it, I think.

31:40Josh Clark:Please, can we talk about baseball?

31:42Chuck Bryant:No, not that kind of divergence. Like deeper into chemistry kind of divergence.

31:47Josh Clark:Okay, I'm going to go out and think about baseball.

31:49Chuck Bryant:Okay, so that whole model that Niels Bohr gave us of like the planetoid nucleus or the sun-like nucleus and the planetoid electron orbiting it, that is really off. That's not at all what they're like. It's good for people who don't really care about this kind of thing to walk around thinking. But when you actually start to try to understand the periodic table, it really gets in the way. So if you can kind of throw that out and instead think of electrons as not particles like planetoids. They're actually waves of energy, right? And they like to orbit atoms because their negative electrical charge is attracted to the positive electrical charge of the protons.

32:35Chuck Bryant:That's why they're orbiting or flying around that nucleus. But they don't do it in like these tight little orbits like a planet does around like the sun. Instead, they inhabit three-dimensional areas that follow predictable shapes depending on the energy level of that electron. You can say what shape it's going to follow around that nucleus. But you can't say where it is at any given point in time, thanks to our friend Heisenberg's uncertainty principle. Heisenberg said you can know the velocity of an object or you can know the location of a quantum object. You can't know both. And because we know the energy of an object, we can figure out its velocity, its speed, like an electron, which means we can't know where it is.

33:28Chuck Bryant:So these orbits actually are where they may be 90 % of the time. That's what an actual electron orbit is. And again, it follows these weird, cool-looking little three-dimensional, four-leaf clover shapes. Just really neat. And depending on the energy of the electron, it's going to inhabit a specific place 90 % of the time around the nucleus of that atom. either close to the atom, further out, further out, depending on the shell that it's associated with. And the block is where the highest energy, the outermost electron, is in that position. And again, it's denoted by S, P, D, and F. And it gets way more arcane than that.

34:13Chuck Bryant:But all you have to remember is that when you're looking at blocks, they're talking about the specific location of the most energetic electron. And again, since the outermost electrons are where all the action happens, the most energetic of the outermost electrons are really where the action happens. And that's why it's become a little more sophisticated, a little more refined over time, thanks to the addition of quantum mechanics in our understanding of the atom. Are you there, Chuck? Did you go outside?

34:48Josh Clark:Sorry, I just came back in. I didn't actually think about baseball. I was just kidding. I watched an entire baseball game. Oh, who won? I have no joke. My brain is too mushy for a joke right now. No, I actually listened to that and I learned from you. So I appreciate that.

35:06Chuck Bryant:Thank you. Because I felt like I was hanging from a trapeze by my fingernails.

35:11Josh Clark:Well, I was underneath you with a net. That's all I'm good for.

35:14Chuck Bryant:Thanks, buddy. I appreciate it. And by the way, I didn't want to just walk past. That's all you're good for. I just couldn't even bring myself to recognize such a dumb thing that was said. I appreciate that.

35:26Josh Clark:So the final thing we got to talk about is kind of brings it back to the beginning of how they originally just started to think about grouping things, which was by their atomic mass, the sort of very basic thing that they first thought they could use as a grouping device. And they still will indicate the atomic mass on most periodic tables. but the atomic mass is actually a weighted average of the amount of protons plus neutrons, but it depends on how abundant different isotopes in that element are out in nature, and it's not always the same. So carbon is a great example that Livia used. It always has six protons, usually has six neutrons, but sometimes can have seven or eight.

36:07Josh Clark:So instead of having an atomic mass of just 12, six plus six, They take a weighted average, and it weighs out to 12.011. So if you see those numbers with a decimal point, you can understand that that's because it's a weighted average and not just a locked-in number.

36:25Chuck Bryant:Yeah, and it doesn't necessarily have much to do with the periodic table, but you mentioned isotopes. And all those are is an element with more or less electrons than it has when it's stable in a neutral charge. If you take away an electron, it has more positively charged protons than electrons. So that's a positive ion. If you add an electron, like say fluorine wants to do, it becomes a, it has more electrons than protons. So it becomes a negatively charged isotope. So those are possible too. But just bear in mind, you're not changing the number of protons. Because if you do that, you have a new element, you're just changing the number of electrons, either adding or taking away.

37:05Chuck Bryant:And one of the other things about the periodic table is you can point to different sections and be like, those are the ones that form positive ions because they give away their extra electron. Those are the ones that form negative ions because they attract extra electrons than they normally have in their neutrally charged state. That's another thing that you can just point to at the periodic table.

37:27Josh Clark:Pretty amazing.

37:28Chuck Bryant:It is. I mean, the fact that people have figured this out is just hats off to all of the scientists that were involved in this over the years.

37:36Josh Clark:Yeah. I say we take a break. Sure. And when we come back, we're going to tell you about how things got very interesting in terms of the periodic table in the 1930s right after this.

38:28We'll be right back.

38:29Chuck Bryant:kids love. Download it for free. You know that pile of clothes you've been meaning to deal with? Yeah, same. That's why I love Trashy. It's the easiest way to clean out your closet, send your clothes somewhere better, and actually get rewarded for it. No more letting things sit around or wondering what to do with them. You just fill up a take-back bag with clothes you don't wear anymore, send it in, and Trashy takes care of the rest, keeping it out of landfills and giving it a second life. It's such a simple way to feel good about clearing space and doing something better for the planet. And here's the best part.

39:05Chuck Bryant:You earn cash rewards back for every bag you send, which makes it even easier to stay consistent. You can check it out at Trashy.io. Plus, with Trashy Unlimited, you can get unlimited bags for just$48 your first year. An easy at-home clean-out system, so you can stay on top of it all year long. Clean out, donate, earn rewards. Head to trashy.io to get started today. They track. They target. Prices can climb. Startpage is the private search engine that helps keep what you look up online from becoming a price tag. Try Startpage at startpage.com. That's startpage.com.

39:57Chuck Bryant:Chuck, I feel like we made it through the hardest part. We're out of the woods.

40:02Josh Clark:I'm shaking a little less.

40:04Chuck Bryant:I am too.

40:06Josh Clark:But I won't fully relax for another 15. Just hang in there. 10 to 15 minutes.

40:10Chuck Bryant:Hang in there. We'll get it.

40:12Josh Clark:All right. So what happened in the 1930s?

40:14Chuck Bryant:Oh, well, a guy named Dr. Lawrence, I can't remember, but the Lawrence Livermore Laboratories, named after him in part, invented particle accelerators, where you use incredible amounts of energy to throw trillions of particles of different weights or specific weights at a target atom. Tell them what Einstein, how Einstein described this process.

40:39Josh Clark:Like shooting birds in the dark in a country where there are only a few birds.

40:43Chuck Bryant:Right. Like the chances of you actually having a collision are so remote that you, like they're almost indescribable mathematically. But if you shoot trillions of particles, you really increase your chances of there being some kind of collision. And when you collide a one particle, one atom with another atom with enough energy, they can combine. And when you add proton to proton, remember, you get a new element. And so with particle accelerators, they were able to start creating elements that you can't find in nature. And they started doing this all the way back in the 1930s. And this research is what actually directly led to nuclear bomb.

41:22Chuck Bryant:Apparently, when Einstein heard that Lawrence had created this particle accelerator, he advised FDR to start working on a bomb because it was now a thing. Like the world had just been prepared scientifically for a bomb to exist soon.

41:39Josh Clark:Yeah. So lab created elements, like you said, started being a thing in 1937, anything past uranium on the chart, you cannot find in nature because it decays much too fast to even be around and know it's a thing and study. But so anything past uranium is lab created. And in 1937, technetium was the very first blank spot to be filled in with a lab created element as number 43. nuclear bombs that you mentioned. When they started doing the nuclear tests out on the Marshall Islands in the 50s, they would send planes out into these explosions with filters on them to scoop up unusual atoms and discover potentially elements.

42:28Josh Clark:That is how we got element 99 named Einsteinium. And I guess we should talk a little bit about the naming because the IUPAC actually has rules around this. It says new elements have to be named after a, and this is very interesting, a mineral, a place or a country, a property, or a scientist, or a mythological concept, which is fascinating. So we have some of the latest elements, I believe in 2016 is when we got 113 through 18. We got the element Tennessean because it was they were institutions in Tennessee that led to the discovery of this super heavy element. And so they named it Tennessean.

43:12Josh Clark:And most of them sort of follow that naming convention.

43:15Chuck Bryant:Yeah. Nihonium is named after Nihon, which is the Japanese name for Japan. A Muscovian is named after Moscow, where the lab where that was created. in Oganison. Oganison? Oganison? Oganison. That's what it is. It's named after a guy named Yuri Oganesian, who is a Russian, essentially, element hunter now. He has got tons of funding behind him, has set up new particle accelerators with more and more energy, and is bashing things together in the search for entirely new elements that not only don't exist on Earth, They may not exist anywhere else in the universe. They may only exist theoretically until Oganessian manages to smash the right atoms together to create those elements for a picosecond.

44:08Chuck Bryant:Like they're so unstable that they last almost no time at all, which makes them totally useless to us.

44:15Josh Clark:Yeah, as of now.

44:16Chuck Bryant:The fact that, like you said, they predicted, I think it's going to go up to 173. Yeah. And we're at 100 and what?

44:24Josh Clark:18.

44:25Chuck Bryant:Makes people like Ognessian just crazy. Like they want to find them all. And he actually found a couple of those most recent ones that were inducted, I guess, in the periodic table in 2016. Yeah.

44:40Josh Clark:And this is kind of cool, too. Ognessian apparently wanted to name that element Stardust in honor of David Bowie, but it didn't fit the naming criteria.

44:51Chuck Bryant:Oh, yeah?

44:52Josh Clark:Yeah.

44:53Chuck Bryant:Too bad. So sad.

44:54Josh Clark:Yeah, too bad. So as far as the sort of the coda on this, Libby is keen to point out that there are gaps in the framework still. There are issues when you look at the periodic table. You needn't only look at the very first one, hydrogen, at the far left of the table. It's there because it has that one electron. But it is not like any of the rest of its group because the rest of them are all alkali metals. It's actually more similar to something like chlorine, which is in the second column from the right. But, you know, there's still debate on like. It's not settled on where things should be placed on these various.

45:36Josh Clark:And there have been, you know, there are alternative tables that people have put out over the years with different tweaks, some small, some large. And it's pretty interesting, I think.

45:44Chuck Bryant:And there's also that two period section that's always removed from the rest of the periodic table. It's put down below it. But those two sections actually go in.

45:57Josh Clark:That's the F block, right?

45:58Chuck Bryant:Yeah, the bottom two rows. So they come after, I think, barium and just go all the way over to, oh, I can't remember the other one. But imagine that the periodic table looked like it did, but then the bottom two rows were about twice as long as they are now. It'd look weird. And it's because you would take that lower F block and put it into its proper place if you're arranging these things by atomic number. But the reason why the F block is pulled out is because those two rows of elements, the actinids and lathinids, I think, they might like follow an atomic number in that way, but their properties are totally different from their periods or their groups.

46:45Chuck Bryant:And the reason why is because they're the only two groups that have the F position subshell filled by an electron, which completely alters their everything. It's just different than all of the other ones. And it's different enough that they just basically removed it until they can figure out where it should sit. Because depending on how you interpret where, like how the periodic table should be laid out, they should go here, they should go there, or they should just stay out like they are now.

47:17Josh Clark:Yeah. There are some, and it's kind of fun to look some of these up if you want to see some kind of cool, at the very least, just aesthetic examples. And then they're not just like, oh, this looks cooler. it makes sense to the person who has put out this whatever alternative or alternate periodic table. Like in 1949, Livia found one from Life magazine that is a spiral, and there are quite a few different spiral or spirulic designs where you have hydrogen at the center, and it's sort of like racetrack shape. If you look at any, just look up spiral-based periodic chart, and they're very nice to look at.

47:57Josh Clark:I imagine they're much, much harder to sort of make sense of and read unless you're the person who made it. Or a chemist. Yeah, a chemist would still probably be like, well, why are you doing it that way?

48:10Chuck Bryant:I liked it the other way.

48:12Josh Clark:Or that 3D one that Timothy Stowe came up with that I think physicists are pretty keen on that has three axes of different colors that represent quantum numbers that describe the electrons. But it's, you know, if you look at a 3D version, that's kind of cool, too. But if you find the one, the traditional one confusing as a non-chemist, just try looking at any of these other ones. It's really confusing.

48:37Chuck Bryant:Yeah. And it's all it is, is it's saying, well, actually, no, I think we should arrange them so that they're connected more by this property, like electronegativity or they're shiny or they're pretty. I like this, these elements. And so we're going to put them together. These are my favorite elements. It's just kind of like that. And so you can bend them in all sorts of weird shapes. Yeah.

48:57Josh Clark:I have my own periodic table I've designed.

48:59Chuck Bryant:Oh, yeah?

49:00Josh Clark:And it is just a big black block. And in Times New Roman and yellow lettering in the middle, it says, who gives a S?

49:10Chuck Bryant:Right. I would have imagined it was a traditional periodic table, but scratched out with a pen almost violently.

49:17Josh Clark:No, that's good. I like that better. I'm going to change mine.

49:19Chuck Bryant:I've got one other thing that doesn't – it has a lot to do with everything but not anything we're going to go into. But there are some, especially those elements that don't occur in nature and they have to create in particle accelerators. Yeah. But also some that occur in nature like gold and mercury are two good examples. they have electrons that spin so fast that are moving at such incredible energies that they actually are like a significant fraction of the speed of light that's how fast they're going and it doesn't matter whether you're talking about like a photon or planet or a black hole or an electron anything that has mass and can move at anything like half the speed of light is going to actually bend time and space.

50:09Chuck Bryant:And so for some kinds of elements that have relativistic speeds, meaning their electrons travel close to the speed of light, they have all sorts of freaky deaky properties. It's why gold is gold. I'm not going to get into that. Just trust me, it's why gold is gold. But also it means that if you could go into those atoms and just kind of exist in them as if they were a universe, you would see that time and space was bent compared to how time and space exists outside of those atoms, like on our level. That's what atomic scientists have figured out, and it's actually kind of having a mind-breaking effect on the periodic table to an extent.

50:53Chuck Bryant:Amazing. I think so, too. That's it, Chuck. We did periodic tables. It's done. You did great. Oh, boy. We don't have to do it again? No, I don't think so. I hope not. Yeah. What is this, Murphy's Law? Well, since I said Murphy's Law and Chuck laughed because he got the joke, you may not have him. That's okay. That means it's time for listener mail. All right.

51:17Josh Clark:I'm going to call this a very quick follow-up from our Halloween episode. As we record this, it is actually Halloween. So that has just come out today. And we have something from Owen that perhaps explains something that we kind of wondered about. Hey, guys, once again, loving the yearly spooktacular. Figured I'd mention my take on what the hermit meant. Hermit? Hermit meant when he said the man's eyes didn't match his mouth.

51:44Chuck Bryant:Oh, yeah.

51:45Josh Clark:I think it might have something to do with honesty, like the words of encouragement were somehow disingenuine. That lined up with the idea that the hermit is sort of seeing flaws and faults. That makes sense to me. Eyes didn't match his mouth.

51:57Chuck Bryant:That's like the best explanation I've heard so far. It's also the only explanation, but it's a good one.

52:02Josh Clark:I think that's totally it. And Owen says, regardless of whether that's the author's intent, I'm using the description in a song I'm writing. Oh, cool. So thanks for the inspiration. And in all honesty, the voice work is on point this year. That is from Owen.

52:17Chuck Bryant:Thanks a lot, Owen. Here's some inspiration for the musical part of your song. do do do do do do do do do do do do do do do do do do do do do do do do do do do do do do no uh if you want to be like owen and write in to explain something to us we love that kind of thing you can put it in an email and send it off to stuffpodcasts at iheartradio.com

52:45Josh Clark:stuff you should know is a production of iheart radio for more podcasts my heart radio

52:49Chuck Bryant:visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.

53:19Chuck Bryant:songs, and shows. Lingo Kids is the number one entertainment platform for young kids. So no dinosaurs? And dinosaurs! Lingo Kids! Everything kids love. Download it for free. You know that pile of clothes you've been meaning to deal with? Yeah, same. That's why I love Trashy. It's the easiest way to clean out your closet, send your clothes somewhere better, and actually get rewarded for it. No more letting things sit around or wondering what to do with them. You just fill up a take-back bag with clothes you don't wear anymore, send it in, and Trashy takes care of the rest, keeping it out of landfills and giving it a second life.

53:58Chuck Bryant:It's such a simple way to feel good about clearing space and doing something better for the planet. And here's the best part. You earn cash rewards back for every bag you send, which makes it even easier to stay consistent. You can check it out at Trashy.io. Plus, with Trashy Unlimited, you can get unlimited bags for just$48 your first year. An easy at-home clean-out system, so you can stay on top of it all year long. Clean out, donate, earn rewards. Head to Trashy.io to get started today. They track. They target. Prices can climb. Startpage is the private search engine that helps keep what you look up online from becoming a price tag.

54:41Chuck Bryant:Try Startpage at Startpage.com. That's startpage.com.

54:46Josh Clark:This is an iHeart Podcast. Guaranteed human.

From the publisher

If you’ve ever wanted to listen to two totally untrained, non-chemists who are fully unqualified to explain how the periodic table works nervously explain how the periodic table works, then this episode is for you. Chemistry majors, be warned.

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