Chem
chapter 1
Scientific Method:
Question → Background Research → Construct Hypothesis → Test by Experiment → Analysis of Results → Draw a conclusion
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Hypothesis is valid Hypothesis is invaild
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Report Results
Its hypothesis is invaild go back and construct hypothesis
Need: Objectivity - a lack of bias
Consensus is NOT part of the scientific method
Terms
Matter: has mass and it occupies space
element: a substances that can’t be broken down into another substance (on periodic table)
Atom: smallest particle of an element
Molecule: a particle made up of two or more atoms
compostion: what atoms are there and how many
what the scientific method is. It's important to know that, because there's sort of a lot of stuff out there in the realm right now that does not follow the scientific method, and you need to know what real science really is. And so, I'm going to outline sort of what the scientific method does. And we will go through a good example of another disk. You start with a question, and then to answer that question, you can do something called background research. Right? Um, so far. So good. After that research, we're going to construct a hypothesis. Once you construct hypothesis, it is necessary to test that high conscience. So you're gonna test by experiment. Then, once you do all these experiments, you have a lot of results and experiments, and you analyze it. So the next comes analysis. results. After you analyze the results of your experiments, you're going to withdraw conclusions from that. Now, I'm going rapidly, but I'll explain that for a second. all conclusions. Now, the two conclusions you draw can be separated into categories. Your hypothesis is valid. Or your hypothesis. is invalid. And then once you get that, you report results. Now, there's one more pathway that I need to show to sort of bring this illustration full, and that is this. If you conclude your hypothesis is invalid, you can go back to this step to construct a new hypothesis. you go through it again. All right. So there's the general idea of it. Now, I'm going to go through a very good example of the scientific methodism, a very good way of pointing it out. Um, to show, um, let's see, I hope I can remember all this, some super real things, but uh, to really show what each of these steps sort of means. And maybe this is closer to biology. Anyway, hear of the disease called rickets. Yeah, so some of you have, this is a disease that happened to children a while ago, they had their bones, and their legs would fall out, and it was, It was a disease that we wanted to figure out what caused it and how it could be cured and all that kind of stuff. So, the question then was, you know, what is causing this disease called rivet? What, you know, what isn't, and how can we fix it? So background research was done. And in the research of the background, it was discovered that if children took a decent amount of cod liver oil, they wouldn't get crickets, right? So, I said, wow, that's interesting. Something in the cod liver oil that is helping children not to get rickets. And so, I don't remember the name of all the scientists, so I'm going to skip over that. But it was proposed because cod liver oil is extremely rich in vitamin A. It was proposed that the vitamin A, in cod liver oil, was what prevented rickets. That was the hypothesis, now hypothesis, is sort of an idea and a theory put forward. So the theory was vitamin A helps cure ricket, because that's what's in the comp or for coin. Now, they're going to test this by experiment. So what they did was they took some cod liver oil, and by some process, they removed all the vitamin A from the copper oil. And once they remove the vitamin A from the cod liver oil, they continue to give the cod liver oil, the children, to see what happened. Okay? So that was the experiment that they were testing with some. Now, the result of the experiment was that it cured rickets. It still cured gritness, even after you removed all of the vitamin A from the controver oil. So the analysis of the results, and the conclusions that were drawn, was, well, it's not the vitamin A that is curing the rickets. So... The conclusion was that that hypothesis was invalid. It is not vitamin A. I don't know if this is in the way of anyone C. It's not vitamin A, it's causing rickets. So boom, boom, boom, go up here, and we'll try constructing a new hypothesis. All right. Well, after doing some more research, it was discovered that lots of times if children were exposed to sunlight, they could avoid bricks. And then the cod liver oil was analyzed again, and it was found that it was not only very high in vitamin A. It was very high in vitamin D. Okay? And so the new hypothesis was that it's not the vitamin A that's curing, right? I guess it's the vitamin D that's pure in the. All right? So... did the same type of experiment, I believe, if I remember what I read a while ago, and remove vitamin D from the continental oil. and found that when this cod liver oil was administered, it did not prevent rays. Okay? And then discovered when they did give vitamin D instead of cod liver oil, children, that did cure them of ribbons. So, that was the experiment. The results were, it looked as if vitamin D was definitely the culprit that cured the ricket. So the conclusion was vitamin D is what George Ricketts. And they said that the hypothesis was valid, they published it, and since that time, your gets has not been a very, very sort of serious problem, at least for most of the 1st world, because a lot of newborns are now given vitamin D right away so that they don't have to worry about anything. Any questions about that sort of example of the scientific method? But you can see that there's sort of a process by which you hypothesize it to all this. I hope that clarifies this. Any questions or I go on? All right, now a couple things about the scientific method. And this is very important as well. One thing you need, if you're going to do this, is objectivity. Anybody know what I mean by a need opportunity? Yes. Hmm? Like measurable ways of the data. That could be a part of it, but that's not exactly what objectivity means. You're going to notice that I do ask you questions about this things. So I do kind of force you all to get involved in this. So anybody else? The reason why you're researching? Uh, not exactly. Anybody know what objectivity means. What the word objectivity means? Because that's a problem. If you need objectivity, you don't know what it means, then that's gonna be a difficult question to answer. Objectivity means a lack of bias, all right? So when you say you need objectivity, you can't go in there with preconceived notions. You can't go into your experiments and stuff thinking, oh, this is what's going to happen. That's what we mean by objectivity. Any questions about that? all right? You can't go into an experiment saying, I'm looking for this and nothing else kind of with it. All right. Now, here's a big one because this goes against a lot of what we would hear in popular culture. And that's this. Consensus. not part. of the scientific method. Okay. In case you didn't know, I am a scientist. When I hear, people start talking about, well, you need to accept this sign. There's a consensus, says, That's a rip flag. like, no, that's meaningless. Consensus is a meaningless thing. You do not cite consensus as a reason to believe a scientific theory, right? Yes. Consensus has nothing to do with what's true and what's factual. All right? If something is true and factual, all right, then this is, if we take this to the bank, the argument will not be for consensus.
-The scientific method consists of the following steps: Question → Background Research → Construct Hypothesis → Test by Experiment → Analyze Results → Draw Conclusion. If the hypothesis is valid, report results; if invalid, revise the hypothesis and retest. Essential to the scientific method is objectivity, meaning a lack of bias, and consensus is not considered part of it. Key terms include:
Matter: Has mass and occupies space.
Element: A substance that cannot be broken down into another substance.
Atom: The smallest particle of an element.
Molecule: A particle made up of two or more atoms.
An example illustrates the process: Initially, a hypothesis suggested that vitamin A in cod liver oil prevented rickets, but experiments revealed it was actually vitamin D that provided the cure
Properties: Physical: a property of a sample that can be observed without a change in compostion
Chemical: property of a sample that can not be observed without a change in compostion
Changes : Physical: change in the sample without a change in the compostion (example: breaking a pencil, boiling water)
Chemical: change in the sample with a change in compostion (example: iron oxidizing, lighting paper on fire)
Matter
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Pure substance Mixtures
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Elements Compounds. homogenous heterogenous
O2 S8 SO2
Pure substance: will have a fixed/constant composition
Mixture: will not have a fixed /constant composition
Elements: only has one element in it
Compounds: has more elements bonded together
Homogenous: uniformed throughout (ex:ocean water)
Heterogenous: not uniformed throughout (ex: piece of granite)
Brass is a homogenous mixture
alloy - a mixture of metals
All solutions are homogenous mixtures
Scientific Notation #.## x 10^n
1-10
what gets measured?
mass - measured in grams g
volume - measured in liters L
length measured in meters m
mili: 1000 (one thousand) 1m=1000mm
centi: 100 (one hundred) 1m = 100cm
kilo: 1000 ( one thousand) 1000m = 1km
Temperature: °C, K
K = °C + 273.15
0 K all motion stops
kinetic energy of particles
Mass: measurement of inertia
weight is a force
F=ma
a=F/m
Density: d= m/v = g/cm³ or g/mL
Accuracy: how close you are to being correct
Precision: when mulitple values are close to each other
Sigificant figures
2001: 0’s between #’s are significant
328000: 0’s after # is not significant unless there is a decimal
0.000328: 0’s before # are not significant
328.000: 0’s after # are significant when theres a decimal point
32800.00: 7 sig figs
decimlas 0=significant doesn’t matter where it is if its in the number
molecule is now, right? It has to be a particle, an individual particle, if it's not molecule. All right, so here we go. Uh... We'll just start off again. With another word... If I ask you, what is the composition of salt? Or what is the composition of water? What am I asking? What elements are in there? Correct. In other words... We'll say, just, what atoms are there, right? And what else? Let's try, sure. Um, No, because the structure is independent of the composition is. But you need more than just what atoms are in it, right? Okay. What? The type. Nope, that doesn't affect the composition. In other words, yes, how many of each there are? Yes, very good. That's the other one, right? There's water, H2O, there's hydrogen peroxide, H2O2. They both have the same atoms, hydrogen and oxygen, but the composition is going to be different because one has a different number of oxygens than the other, okay? So what atoms are there, and I'll put it this way, and how many, all right? All right, that's, that's what is meant by composition. So, when I ask, what's the composition of salt, you would say, you know, one atom of sodium, one atom of chlorine, that's what composes salt. By the way, in case you didn't know, that's what salt is, right? Salt is sodium chloride, that's this, all right? So that would be the composition of salt. And again, salt is another example of a compound that does not have any molecules. There's no molecul or salt. Any questions so far about any of the terms that I've given you? So you need to know those things so that when we communicate using chemical language, you're going to get really into this in the next chapter. You're gonna hate it, but you know what I'm talking about, and, you know, you're talking about. All right. Next, why don't I... Now, I'll just go there, properties. Okay. I'm talking about water I'm talking about. E of these has certain properties. Um, there are two different types of properties, there's physical properties, and... and I call properties. Now... I'm going to skip over what the definition of physical and chemical properties are, because it's easier to understand these if we do something different first. And that is, if we talk about changes, and for changes, there's gonna be physical changes and chemical changes. Okay. And again, this is when I mean, and I go here, and I say, Okay, give me an example of a different type of change. What is a physical change and what is a chemical change? Yes. A physical change could be, like, depends on how. Correct, right? Being a pencil in half is an example of a physical change. Why? you're changing the physical shape. And you're not changing what? Good. The structure, like, again. Very good. You are not changing what it is, right? It stays a pencil, maybe broken a hand. But I guess so, right? One will have an eraser, one will not. Right? So that's what a physical change is. It's a change that does not incorporate also a change in the substance, all right? So let's put that down, all right? Physical change ends up being changed in the sample. Let's say, change. And the sample without a change... in let's be much specific. The composition we just did composition. So, so, for example, uh... I'll just ask you this, is boiling water, taking liquid water and boiling that. Is that a physical change? Or not. Yes. You say yes? Why? Why us? You guys are very soft spoken. What was that? Correct, right? You're absolutely right. In other words, when you boil water, it starts out as a water H2O, ends up with water. You're not changing that. changing the state, all right? And that gives you another example, a change in state, is a physical change. It's not chemical change, right? Because you have the same compound, the same composition. So that's what a physical change is. Can someone give me an example of a chemical change? Yes. A change in color? Uh......................... Oh, gosh. I have to think about this. Changing colors. This is much more complicated than yours, thank you, Jesus. I'm not gonna... Yes, please. I suppose, in a way, it is, because there's some has to be some type of... Keep it ignoring that one. I'm gonna steer clear from that, 'cause sometimes there's results from, gosh, I don't know if it's considered, I suppose it is chemical, but, uh, ligands and stuff like that. But, but, um, is that what you're talking about, Lincoln? Totally. That could be, yes, uh, but, uh, let's try one that's a little more obvious, how's that? Yes. Like, you can bake a cake? If you bake a cake, oh, gosh, you're actually coming up with chemical changes of things that aren't very chemical. Let's see, if you bake a cake... Whatever it is.. That's a job because... Are you changing both the composition of a cake? I mean, there is a angry, actually. What about? Isn't there a chemical reaction when you bake cake? Kind of. Like an aches. Yeah, but... We're making things hard to say what the composition of a cake is, you know what? not like, I say, a cake is always, you know, this much milk, this much eggs, this flour, this would, da, da, da. I need to get a certain kakey-doo-doo da. Sometimes, but you can vary the amount of eggs. You can vary the amount of milk and flour, so they'll have to wait, right? So, yes. Something oxidine, like iron wrestling or something. Okay, there you go. I can deal with that one, right? Iron rusting, right? You have a piece of iron, you leave it outside and rusts. That's a chemical change because what you're doing is you're changing the composition, right? You're changing it from metallic iron to iron oxide. All right? If you light a piece of paper on fire, is that a physical or chemical change? Hmm? Chemical. Both. Nope, it's one or the other. It's definitely one. Hmm? You only have you have a 50-50 chance, it's only 2 choices, right? Damnable. Thank you, it is. It's a chemical change, right? You are changing the composition of that paper. It's no longer a paper. It's something else to file of ashes. All right? So, chemical changes, you can start figuring out what the dynamics of that is. If physical changes a change sample without a changing composition, what do you think the definition of a chemical change? Changing the temple with the change. Very good, that's exactly correct. That's what it is. Accompanies with a change in competition. So it's a change in the sample. With a change. And. Okay. Now, this leads us to property... more easily than just going through property. So, we see, then, that certain... Now there are certain chemical properties, all right? And we've discussed, some of them, like whether something oxidizes correct, that's a chemical property. Whether something is flammable, that's a chemical property, right? Because these are properties that will, uh, change. We can get a better handle now on properties. A physical property now, property. And this is gonna be very similar to the change. That's why it's good to do change first. Of a sample... That can be observed. You can probably figure out what the rest is. Now... change... in composition. So you can observe a physical property. change proposition. A chemical property, then, is gonna be a property. Well, a sample. That. Cannot be observed. Without... the change in composition. Okay, so now we get a better idea on what some physical properties are when some chemical properties are. I said, physical properties are changes to state, changes of shape, often, changes in size, stuff like that. Chemical properties are changes, such as or chemical properties or properties, such as climbability, oxidation, something a little oxidize or not. whether something is, let's say, corrosive or not, stuff like that. Right? Any questions about chemicals, properties, chemical, physical changes? Okay, good. Now... let's go into Matt. is that the chemistry might be called a study of matter. So what I'm going to do here is sort of go into a what's called a classification. So we have all matter here. Now, all matter can be broken up into two separate categories. They want to grow, one, two... pure substances. Fixtures. So we have these two. So matter can be broken up into these two sort of general properties. Actual properties can further be broken off into categories. Pure substances can be broken up into either elements. Or... And mixtures can be broken up into... Genius mixtures. Heterogeneous. Okay. So... let's try to figure out... ways of defining what a pure substance is, what a mixture is, all right? And then after that, we can go into the subcategories. What is the difference between what would be a pure size, a mixture? In the deal. This is kind of, yes. I already came like that, and the mixture was, like, really accomplishing it. What do you mean, what do you mean, already came like that? It's naturally sound. Yeah. Oh, naturally found? So, soil? Exactly, soil's not pure subjects. Yes? And someone that has like the same composition throughout. Uh... A little more specific. That's true, but a little more specific. I'm asking, what else? Not just the same route, but what? Because you can have mixtures for the same composition. But what would make it if pure substance? Great part. Well, you can break your substance apart. And I'm sorry. Yes? It's just, like, one element, and I can make sure people... Well, no, we could be compounds too. What do those two have in common? Not only do they have a uniform composition, composition is the key, but they have what kind of composition? I'm giving you more of a hint now. What? An equal? No, they don't have to have equal competition, right? H2O is a pure substance. That's too high because one oxygen not equal. That makes substance. What? What makes it into yourself? That's what I'm asking you. Yeah, okay. You can't trick me with those trick questions. Almost said, yeah. So not only does it have uniform composition, it has a blank composition. Simple. No, not... Yes? Single composition. Single? What do you mean single? I mean, like, in a pure substance, there's people, I, or something, and they make sure it's in different elements. Oh, gosh, I need to come back, because... We got any silks of locking. She's probably gonna be away in the back here, yeah? Um, in a period of such a thing, you won't be fine, like, more of an element, or it's more sort of... So the composition is what? Single's not a great word. In other words, H2O is a blank company. Unique? Uh. Like, water is very substance, because it only have HQL. Like that's what I'm trying to do. I Yeah, so it's composition is what? It's true, it is unique, but that's... Not quite the right description. All right, here's the question that should give away. Does its composition change? No. So it has one kind of composition. Huh? Oh, I have to teach you more words, huh? Yeah, we only have. So what does it mean when it doesn't change? Has a what composition? Yes? Consistent. Uh. Consistent. Better than that, what... It kind of sounds like that. You can use a word that kind of sounds. Constant. There you go, constant. That's better, right? I would even say it has a fixed composition, right? Or a constant composition. So, pure substances, I don't think I have to weigh all this, but now, Pure substances will have a fixed composition, all right? Which means mixtures will make something a mixture. They don't have... Very good. They don't have a concert or a fixed composition. You see that? Right? So, water will always have two hydrogen, one oxygen. That why it's a pure substance. Okay? Carbon dioxide will always have one carbon, two oxygen. It's a huge substance. Okay. Mixtures do not have constant composition or fixed composition. Any questions so far? All right, so pure substances are separated into elements and compounds. This part should be pretty straightforward. How do you tell the difference between element and compound? Yeah. Wow, man. Okay, that's good enough. That's easy enough, right? An element only has one element in it, right? A compound has more than one element on it. Yep, right? So, we know that gold is an element, but we also know other things. We don't oxygen element. I'll just write this down here. This, by the way, is a formula for oxygen. It's actually open two. So it's two oxygen panels bonded together. It's still an element, though. It's not considered a compound, all right? It's elemental oxygen. It doesn't have to just have one atom in order to be considered. You know, sulfur, by the way, one of the forms of sulfur has paint. sulfur behind That's an el, okay. However, if you have so two, that is a compact. Any questions about that? That's pretty easy. What compound is that, too? Sulfur dioxide. Next chapter, that's when you're gonna learn how to name all these things, so you look forward to that. That one was pretty easy. Yeah. All right. Now the tougher question. In the realm of mixtures. What is the difference between a homogeneous next year? And a hever? Yes. What do you mean by that? The same stuff. Like, um... It's like, I don't know, but salad dressing. Right? Sounds like us. She's hungry. I wish she... No. Yes, go ahead. like organized distribut. Okay, how is it organized or distributed? Oh, this is right, but, like, homo genius is, like, a small one, like, distributed. Oh, okay. That's very good. That's excellent's actually what it means. Well done. Homogeneous means it's uniform throughout. All right? Which, now you know what heterogeneous mixtures are, there, what? Not uniform. Very good. You can figure a lot of these things out. Yeah, not uniform, but outcome. Throughout, sorry. Um, can you give me examples of homogenius and heterogene? These mixtures? Ocean water. Okay, what type of mixture would that be? Good idea. Only. Very good. That's correct, right? If you get a bucket of water, you can see, one drop over here, one drop on the bottom is going to have the same composition to it. So it's uniform throughout. It's not like one part is different from the other. Do you see how that works? Yes. Would, like, boil, and water being had or...? Uh, if they don't mix too well, yes. Like salad drif sand, yeah, right? Depends on the salad dressing, right? Italian. Why? Yeah, you got a little bit on the, you have all the, you go to the malls. Then you shake it up, and then... But what do you know? But it's still, like, separated. It's, like, real and water don't. No, they would be heterogeneous, because they also have herbs and stuff, right? point to an herb is different from pointing to a piece of oil, right? Yeah. So, um... What about a piece of granite? What would that be?? Hetter, Hetter, Register. Very good, right? It would be heorrhenous because you can see it's heterogeneous, right? What's a piece of granite look like? It's basically, like... Typically, it was very... What does that reaction for? It's like Dr. Gross and I said something. I'd expect you'd listen to me, but I said so. But what's a piece of ground? Do you know what a piece of granite looks like, I hope, right? What's it look like? There's usually a different color. Different what? Types of wine? Crawl. That's okay. Different types of rock. It speckled, right? It's kind of a speckled kind of a thing. Has, like, dark, light speckles. You point to a dark speck. There's one who lights back. There's obviously different, right? So it's not homogeneous, it's better genius. Okay. All right. Um. Okay, there's one more sort of category I want to throw at you. How about... how much we know about that? How about brass? What about this? Oh never. What is it? Out of all four of these things, but how would you categorize it? Pure substance, mixture. A mult genius compound. Yes. I'm misapure substance compound. Uh, no, it's not. It's not a compound. Yes. Yeah. Very good. That's what it is. The homoene mixture. All right? Oh wait. Is brass a methyl? Hmm? Yes. Yes? Isn't it? Is it on the periodic table? No. Is it a medal? No. No, it's not a mess, right? Yes. A minute, too, that was me. Very good. That's exactly what it is, though. I was gonna get to that. But it is something called an alloy. An alloy is a mixture of metals, different metals mixed together, right? Grass consists of mixtures of copper and zinc, mostly, mixed together. But it's a mixture because it doesn't have a fixed composition, right? You can vary the amount of copper, you can vary the amount of zinc, you can make it more copper, less copper, mixed together to make different brasses. Okay? So that is not going to be a metal. It's not going be an element, it is not a pure compound. It is a mixture of what type of mixture it is a genius. By the way, all solutions are homogeneous fixers, right? You can take some solid dissolid water, makes it up, that is a almost used mixture. Alloys are sometimes called solid solutions, right? Because they are solid polish. mixtures, okay? So, you just learn more about what alloys are. So they're not metal, and you'll be surprised at what things are not considered met, right? For example, is iron a metal? You want to take this one for a time? Yes. Yes, it is, because why? It's another... The element is on the periodic table. You can tell. You can see on the periodic cable. Is steel a metal? No, no. No, it isn't. What is it? An owl. It's an alloy, very good. Steel is a mixture of different metals. I mean, I'm sure most of you probably thought of steel as being a metal for this, but it really isn't. Steel is a mixture of mostly iron, but depending on the type of steel, and you've heard there are different types of steel, right? You've heard there's stainless steel, there's high carbon steel, there's, you know, all different kinds, but steel's usually a mixture of most people, depending on what type of steel you have, nickel mixed in with that, and you have chromium mixed in with that, carbon mixed into that. And you create an alloy. Any questions about any of these things so far?. So you have a better idea of how to classify different types of matter. Very good. All right. What next? Yeah, I think I'll just say this. Now, getting back to chemistry, what we're gonna do a lot of other chemistry, especially the lab, is measurement and experimentation, all right? Which is normal, right? You measure things, you experiments, you observe things. going to involve, invariably, cringe and stuff like this, is numbers, all right? It's gonna involve math and numbers and all that kind of stuff. And I know we're all looking forward to that. So what we're gonna do now is I'm gonna start talking about numbers and numbers how they're using chemistry. All right, first things first. Everyone, familiar with something called... Scientific number. Anybody know what scientific locations is already?? Yes? What is it? Well... All right, it is a different way, but what what way? something. Yeah. What's E? X one? Exponent of what? Oh, I know what it meant. 10, thank you. It's an exponent of 10, right? It's a number expressed as being part of 10 raised to a certain power. And I'm gonna be very specific on what it really is. It's... some, let's say, number point, number, number, whatever, et cetera. times 10, raised to something immature. That's scientific notation, right? So it's gonna be some decimal times 10 raised to a certain power. Okay. Now, I'll throw out some chemistry numbers for you. How about, uh, yes. There's a number you're gonna see in Council, 27, 3, 4, 5. All right, how much do you know about scientific notation? If I wanted to express this number in scientific notation, how would I express it? 2, 27, 3, 5, 7, 2, 3... Negative two? Not negative, too. Just two. Positive too, right? Correct. If you have to go this way, one, two, it's positive, and you can kind of know that, because this number is less than this, so it has to be multiplied by 100, to get to this, right? So this is 2.7315 times. And then the second. Okay. Anybody know what the significance of this number is in chemistry, by the way? Very good. Yes. Ben's right. It's the conversion of the greasy to kill them, all right? You'll come up with that. Later on, of course, all right? Here's another number that's significant. Chemistry. 08205. All right, now, if I wanted to express this in terms of scientific rotation, now, that's yours. 8 point. Yes, go ahead. And the 8.205 times the egg. Very good. That's exactly right. I don't know if you've heard of that, but it's 8.205. That's times 10. The minus two. Okay. So if you move the jackpot to this way, then it becomes negative. Notice it's always a number between one and 10 here, right? Notice I didn't write this as 27, or 315, not at the first, right? That's not the way scientific notation is done. Something points on something. It's a number between one and 10. not including. So, we're going to do this this way. By the way, anybody know what the significance of this number is? chemistry. That's okay. We haven't done it yet. nothing wrong with not knowing you yet. You're gonna see that's what's called the ideal gas console, right? But you don't have to worry about that. Now, having written these numbers down, scientific notation, let me tell you what it is not. It is not a way of expressing, expressing notice, both scientific. I would never write numbers like this. in all series. I would write them like this, because it's easier, all right? Scientific notation is just a tool to make writing certain numbers easy. In this case, it really doesn't, all right? So, I would not use scientific notation, but these numbers. However, here's a couple of other numbers we tend to use in chemicals. All right. 2.022 times 10 to the 23rd. Got your number. By the way, anybody know what this community is of this number is? I'm gonna... Very good. This is Avocado now. This is a very famous one, right? Now, let me ask you a simple question. Would it be easier to write this number like this, or would it be easier to write it out? Like this. Obviously, like this. Times 10 to 23 means you have to move this over 23 spaces, being one, two, three, and then 20 zeros after that, all right? Don't ever write numbers like that. Even if you like doing it. I don't like reading them, okay? So put it inside in a notation, that is a tool to use in order to simplify writing numbers. It's much simpler to write that number like that than try writing it down. And here's another one. Please, tell me. No. Should' dis gracious, I hope you never have to write that number. 6.626 times 10, the minus 34. Uh... That means you have to move the desk, well, the other one. One this way, and 33 more zeros this way. And then another 0 point after that, forget, it wouldn't fit on a piece of paper, right? Okay? That would be a very useful way to use the scientific notation or to simplify it, okay? By the way, anybody know what that number is? Then we'll get to that one too, at some point. That's the finest concept, right? So, we get to find something to see that, that, uh, God's going to this. All right. So, you kind of know what scientific notation is now. Now, in chemistry, chemistry is not like mathematics, and that we don't just use numbers. You know what I'm talking about? We use numbers as measurements, which means we usually put units after the numbers. And so... My quick question is... In chemistry, we tend to measure certain things. Maybe what I'm thinking of more is the three basic things. that we measured. Does anybody want to take a gander at what those three things we measure are? Mass is one of them very good. We can measure mass. And when we do, I'm going to introduce you to the metric system here if you don't already know what you probably already do. What units do we tend to use as units of mass and chemistry? Yes, in the grams, we tend to use grams, right? So mass, we measure in grams, and the abbreviation for that... So, we say some number, and when we see a lower KG, after it, you know, we're talking about this many grams of measured masses. Now, there's two others I'm looking for. Anybody else that want to take a guess at another one? Yes, volume? Volume. Okay, volume is another. We also measure volume. Now, what is the base unit of the volume that we tend to use account? Yes. Yes, leaders, right? We use leaders. So volume, we tend to measure in liters. And what is the abbreviation for the leaders? Anybody know? Yes? Capital L, right? So if you see some number, uppercase, L, we're talking about this many liters. Alright? One more. Yes. Uh, we do measure temperature. Okay. But I'm not... I'm not talking about that as one of the basic 3 sort of metric system, putting prefixes after that, and stuff like that. Yeah.. Density, we tend not to measure. We tend to calculate it, right? We tend to measure mass and volume and use that to count. But you are correct in that density will be a unit after a number. What you're missing are very baseball, yes. Great. Uh... We tend not to use weight that often in chemistry. We tend to use mass and stuff. Because mass doesn't change with the gravitational field, right? You're missing the most basic one, right? I think. What? I shot. How far did you walk against class this morning? This is. Okay, very good. Thank you. Distance, right? Mike... And what's the unit of length that we tend to use for the metrics? Meters, right? We can use meters. And what's the abbreviation? Meters. A little. A little yeah. Okay. So far, so good. Very good. Now, because we used the metric system, okay? We get to put prefixes before this to sort of change the unit to measure. You all sort are familiar with. Now, there's a lot of them, okay? Don't worry. I'm not gonna make you memorize all the different prefixes before, like, meters and meters to change. I require you when we know three. All right? Only three. And that's this. Millie... Tequila. Hey, uh, I think it's pretty straightforward, these three, all right? I'm not gonna have you tell me how much, how many meters is in a hectometer, or, you know, a decimeter, a deck? I mean, I don't even remember. so I'm not gonna make human number of those things. But these 3 you should, okay? All right. Let's do, let's do sort of a, you know, vocab thing, word thing again, right? Here's a prefix, Billy. What does the prefix milling mean? We get it from words like millennium. No? Millennium is not small. How many years are millennium?. Isn't it 1000? 1000, yes. It means a thousand, right? Millie means a thousand. So a millennium is 1,000 years. You know, you've heard millipedes, they have a ton of legs. They supposedly had a thousand like. They' want count them. I'm sure they don't have a 1000 things, but they have more than a cent of people get back next. Um, uh, and so, uh, this means a thousand. What's centi? 100. Hundred very good, right? You get that from century. We get that from how many cents, or in the dollar, right? There's a scent means 100. Theoretically, a centipede is on, like, a dozen. Now, kilo, this is what gets confusing. I'll just let you know this also means a thousand. Now, but it's different, all right? In other words, let's take meters, and we'll see what conversion is. One meter, in other words, equals 1,000 millimeters, right? So there's 1,000 millimeters in a meter. And this, one meter also equals 100 centimeters. But when you get to kilo, it means the following, it means a thousand meters, is one of a kilo meter. Right? So what you take away from this is a millimeter is very, very short, and a kilo meter is very long. All right? There's in only one meter, which is about this, right? There's 1,000 millimeters, but you need 1,000 of these longer meters to make one kilo or kilometers. Any questions about how that works? Okay, so try to remember that, okay? That's all that I'm that you need to remember. When we start getting into other prefixes like, uh, micro, you know, doing micrograms, and you start doing, uh, pika meters, stuff like that. You don't have to remember that, I will give that to you, right? Any questions so far, these numerical things, though. Uh, where are we? Okay. Yeah, couple of other things. Just what I'm gonna do next. Because I like, I guess, I like having you actually understand what you're talking about when you do a concept. because I have to do this now. Oh, racism, falls. Okay. Now. No. No. Somebody here mentioned, okay? Yeah, who it was? I apologize. It measured temperature, right? For having said that, but something... We do. We measured temperature, right? So we're going to talk about temperature quick, quick. And it's gonna be a slightly more digital. Thanks. I'm about to start with the same stuff. What units do you tend to measure temperature? Yes. Celsius, that's one. And I heard another one, and Kelvin. Those are the two, right? We tend to measure it in what's called... greasy, Celsius, and Kelvin, just K, even though there's no degrees. And we have a conversion factor between those two, that you're already familiar with, and that's this. If you want a temperature in Kelvin, it's gonna be... that we want to be kind of exact, right? It's gonna be whatever we have in the grease sea, plus 273, 24. 5. Now, something about the Kelvin scale, the Kelvin scale is called the absolute temperature scale. Anybody know why it's called that? It's okay if you don't. This is introductory to a lot of people, because Calvin's lowest temperature, the lowest temple. Ah, see, what's the lowest temperature you can't help? Zero. Zero. There you go. Zero is the lowest. You can go. If you're dealing with degrees C, you're dealing with Fahrenheit, you get negative numbers, right? You know, really cold days here, you can get negative, you know, for Fahrenheit, right? And it's definitely negative degrees C. Kelvin, you can never get to negative numbers. That's why it's an absolute scale. The lowest temperature you possibly get in the universe is 0 degree 6. That's the temperature, or 0 degrees K, 0 K. I'm doing it wrong. A zero Kelvin, right? That's when all motion source stops, all right? That's zero tech. That's the absolute scale. See why that's important a little bit. But here's the difficult part. What does temperature measure? Mm hmm. Kinetic energy of what? Hmm? Okay, if you have a molecular compound, the molecules, and you have an element of the atoms, right? But you're absolutely right. Temperature is a measurement of the genetic energy. This is a good word to remember, because this applies to all little things, molecules, asshole, particles, right? Whatever the particles are, the kinetic energy, that's what the temperature is a measurement of. Here's my next question. Because I like it when you guys actually understand things. What is temperature not a measurement? Yes. Heat, it is not a measurement of heat. So, what is the difference between kinetic energy, particles, and heat, the temperature is not a measurement? And this illustration, I'll give you, will show you exactly what the difference is, 'cause I like you guys actually... Okay. Heat. Heat is a measurement of the energy that something is able to transfer something else, all right? Now, I have a couple questions for you. Suppose I have some boiling water, all right? That means it's at 100 degrees sick. If I take one little drop of that boiling water, flick it on you, what's gonna happen to you? It will probably burn you, yes. Seriously? No, no. No. Little. You probably won't like me too much afterward after that, you know. But you only get a little burn, right? We'll get that. But the temperature of that is 100 degrees C. That will give you a very little burn. Now, switch gears now. I have a giant cauldron to boil before, and I dump it all over you. Now what happens? Order is barely burned. Yeah. You will be much more severely burned. But it's at the same exact temperature as the other one. What does the giant cauldron of boiling water have a lot more of than the drop of boiling water? Yes. Huh? Volume? Well, it has more volume. What does the giant cauldron of boiling water have a lot more of than the one drop of water? What? Heat. That's it. That's what heat is. It takes a lot more heat. Okay, to boil a cauldron of water and then to boil a little drop of water. you see that? If you're gonna pump heat into something, very little of it will go into drop of water. So when I click that on you, it has very little heat, you know, into your hand or wherever it goes. So it's not gonna burn you severely. A ton of heat has to go into a huge pauldron, more than water. So when that's done on you, it has a ton of heat that it can impart to you and burn you very severely. All right? That's the difference between heat and temperature. Drop of water, boiling a cauldron of water, boiling, has the same exact kinetic energy of the particles. They have the same kinetic energy. But the heat in the culmin was much higher than the heat from the board, and that's the difference. Any questions about that? All right, good. So that's your little quick lesson on temperature. Now we get to another one that's kind of hard, I understand. But I like it when you understand this. That's mass. We talked about mass. Now, this is a tough one. Can anybody tell me what mass is really a meshing toe? Hmm? You know, that would be... Well, it depends on what you mean, buddy. Um, volume, amount. Uh, just kind of... Let me put it this way. Yes. I like the matter? Um.. Well, you... you can have different types of matter with very different masses. So, if I have a mass of, like, one kilogram, depending on, it's not a measurement of amount of use, depends very much on what type of animal we're talking about, right? But I'll give you another situation. Pose. And this is why we need to know there'll be massive weight, right? Suppose I am an astronaut, am I right? I'm floating out in space, right? You have the same mask. Huh? You have the same mask in my space in New York. Yes, you do. But it's just a gravitational fold, and the space is different than a very, so you wait. That's correct. So we're still trying to find out what mass is really measured about, right? Yeah, I just don't know how to describe it. Well, I know you don't, but we'll get to it, I hope, right? But suppose I'm floating around space, I'm weightless. My weight is zero. Okay. Now, I see, let's say, a huge boulder floating out in space as well. And I flow toward, I reason myself. You know, I'm out in space, so that boulder has no weight either. That means I should take my one little finger, because it has no weight, I should be able to move it wherever I want. So I float up to the boulder, I put my finger on, I push against it, and what happens?. What? You... Yeah, I end up going this way, right? The boulder barely moves at all. Why is that? You know, because it still has more gravitation. You know, it's bigger. The opposite, what we were saying before, the boulder has more... Wait. Oh, yes. Yes, right. The boulder has more mass. Oh, God. So what is this mass thing that I'm talking about? Why doesn't the boulder move, and I do, if Boulder has higher mass, I have lower mass. What is it then that causes when I push for me to move from the boulder to stay still? This is a concept in physics. In Have you said that? Is that you? Yeah. Congratulations. It's exactly the right answer. Very, very good. In other words, the boulder has a lot of inertia, and I don't, all right? Inertia, if you don't know what it already is, it's the tendency of something sitting still to want to sit still, and something emotional to want to stay in motion, right? That stays out and outer space. That is not depend upon weight is dependent upon mass. All right? Mass is really a measurement. of inertia. Okay. It doesn't depend on a gravitational field. All right? You can have no gravitational feel, and there still will be inertia. If you have this giant boulder out where there's no gravitational field, it's this space, it's still gonna be difficult to move it because it has inertia. All right? If it's already moving, it's gonna be difficult to stop it because it has inertia, even though it has no weight, right? Do you see the difference? Okay, inertia stays with you, whether you weigh a lot or a little, okay? It's gonna stay with you in a weightless environment. It's gonna stay with you in a gravitational field. Any questions about that, but well done. That was very good. Us usually I have to go through a lot more to get you guys ass inertia. That's that's very good. Sure, why not? Theoretically now, if I take something very heavy and drop it, it's a very light profit, which will fall faster. If I'm on the earth now. Now I'm in the gravitational field. Okay, I don't know. Everything? Like a feather one. Ah, but what's the reason the featherwood draws back? Drag. What? All right. Like, the, like, drags, I don't break with her. I heard somebody mumbling. You guys like to mumble a lot, right? Air is just, that's why air resistance, right? That's what the whole reason a plane can fly. there resistance. But yeah, but let's say it's not a feather. Let's say it's a marble and a bowling ball. Very good. They will fall at the same time. Okay? Now, it may go against your intuition thinking, well, the force of a bowling ball, right, is going to be much higher being pulled toward the earth in the force of a marble. Does that make sense? And it's true. It does make sense. The weight, which is a measurement of, I didn't ask you this, but let me ask you this, what is the weight really a measurement of? Massive gravational. Which is all day. I mentioned it before, so it should be easy for you. It's a.. I just said you didn't pick it up, huh? No, I guess not. Begins the letter F. Wait is a... Forrest, yes, of course, right? There's a much greater force pulling on that bowling ball. It has a much higher weight. So why do they both fall at the same time? right? This is a very famous equation, because, on the way. And people's MK, right? This tells you that the acceleration of gravity is you have for Emma. And we see, because they fall at the same time, that acceleration then is constant. It doesn't change. Now, why is that? Well, it's because if you're just looking at the force, you're not looking at everything. right? You have to also be looking at the mass. Remember what mass is a measurement of? Now, that bowling ball, yeah, has a lot more force pulling on it. You'd think, boom, did you go a lot faster? But it also has a much, much higher max. Much higher inertia, meaning it takes a lot more force to get that big thing moving. You see that? Okay. So, whereas there's a lot more force pulling on that bowling ball, but it has such a high inertia. It needs all that force to get moving. A little marble doesn't have water floors pulling on it. But it has very low inertia. It doesn't need a lot to get moving, right? That's the difference, again, between weight and mass, right? Weight is the force that's pulling on the gravitational field, masses the inertia, that's trying to get it to move, which is why heavy and light things will fall, the same exact rate, if there's no error system. By the way, they did this on the moon, when they landed up on the moon. You've seen... I don't know if you've seen footage of this. They took a hammer and a feather, and they dropped at the same time, and just went, boom, right at the same time. built down. Didn't matter that it was a feather. There was no air on the moons, no air resistance. It fell at exactly the same rate. So there you go. There's your lesson about mass and what it really is and how it's different from weight. Any questions about this so far? All right. Uh... I'll talk briefly about density as well. Did you ever hear the real... What weighs more a ton of feathers or a ton of bricks?' ins same. And they wear the same, right? Because the tone is the weight, right? But the way it's supposed you, is you're supposed to think, Yeah, my feathers are lighter, you know, that doesn't waste money. You know, what you're really thinking in your mind is not that feathers don't weigh as much, but they're much less bought. They have much lower what. Density, very good, much lower density, all right? And density... is always going to be massive. So density tends to be reported for the most part. Grams per cubic centimeter for grand. Mil leader. Which leads me to another question, I bet. being done a lot of this off the top of my head, but Mills will ask you, what is the difference between a cubic centimeter and a milliliter? Well, you can make the liquids and cubic sandwiches. Any of you going into, like, a lot of you are probably going to help profession, right? You're always doing this many CCs of such and such. What do you think CC stand for? Huh? Okay. Cubic centimeter, right? So you can see cubic centimeter? Yes. Well, square centimeters are, yeah. Cubic centimeters is volume. It's kind of a trick question. the same thing. You know that? They're the same exact thing. That is why you could say that. By the way, the definition of a milliliter, in case you didn't know that, is a cubic centimeter. If you take a millimeter by a centimeter by a centimeter cubed, that volume is defined as millimeter, right? So that's how we got that bond. So they're the same thing, but you'll see this sometimes important as this. and sometimes record that just so you're aware of that. All right. I suppose you should be aware of this, so I'll put it up here. Accuracy and precision. We're not making the same thing. Uh. Anybody tell me what the difference between accuracy pursued? Bye. how much you're precise, like, how often you're... See, using both of them now, accuracy. I don't know how to describe it. by itself. Were you gonna? say something? Yeah. You change your mind?. Um, yes. Is precision, like, how close something is to being, like, correct and then accuracy is the amount of time? Yeah. Like, it's almost... A little accuracy is book. I can see how close you are to, like, the target. Correct. How close you are to being correct is an actress. Precision is... If you were precise, then, like... Precision is in precise. Sounds good. Accuracy is incor accurate. I didn't know that. No, I know. If you're throwing darts at a dartboard, this is the best illustration. Do you want to do it? consistency. Kind of, yeah. In other words, if you hit the bull's eye, you're accurate, right? However, if you miss the bull's eye, you're way off to the right, but all your darts are right there, both together. You're precise. That's precision. When multiple values are very close to each other, attach precision. You have a high precision. It may not be accurate, but you have a high precision. For example, if you're weighing something out of balance on site, and you know your, let's say, the thing you win, you know, weighs one grand. But you keep getting 1.5 grams, at 1.49 grams, at 1.4, high one grams, and all this stuff, because there's something wrong with the balance. Like, there's something underneath it, spread it up. You're getting very precise values. They're all very close together. But you're not getting accurate about them, because the real mass is one grain. Does that make sense? Okay, good. So that's the quick definition and difference between accuracy and precision. All right. Where are we, all right? This, here's something, gossip, giving a nightmare, so it shouldn't, it doesn't much easier than anything. Significant figure, okay. Now! You two think this much more difficult than it is, but it's very simple. I'm gonna boil it down to you. If I give you a random number, uh... let's say... How many significant figures does that number have? How did you figure that out? We founded them, right? No problem. Right? You do not have a problem with significant figures if there's no zeros in it, all right? The only problem you have is when we start putting zeros in. Alright? Now. There are three different types, zeros. Let me start with this. One of my favorite movies of all time. It's 2001, Space On Us. There's zeros in that number, but I'm gonna ask you, how many significant figures are in? Number. Four, four, four. And you find this pretty easy, too, meaning... zeros between numbers. Are significant. count. And I don't think you have much problem with that. It's zeros before and after numbers to start giving you, you know, problems, let's say. So. Suppose I give you this. Now I'm going to ask, how many significant figures are in this number? Very good. It's three. Now it's only three, and that's because this is the next rule. Zeros, after the number, is not... I should have done it before, though, first. Uh. I'm gonna have to change that, so... All right. 0.00, 328. How many significant figures in this number? Sorry, three. Three. All right. Yeah, I made it. I should have done this a second. Zeros after... I didn't do that for one, I think. Zeros before, I should have done zeros before the number. are not significant. Now, you're gonna do a different thing. ready? Okay, that's awesome. 328.000. That is six. This is why I should have done the one before, because the rule here is not zeros after the number are not significant. They're not significant unless... there's a... desperate. Then they're significant. And those are the rules, right? I should have done this second. I'm sorry. Significant zeros between numbers, zeros and four numbers are not significant ever. Zeros after the numbers are not significant, unless there's a decimal point. Notice I did not say where the decimal point has to be. It doesn't matter where the decimal thing is. You realize that. So, if I give you 0.00, 3, 2, 800, How many significance figures there? Five Yes. Very good. There's five. Because before the number, they're not significant, ever. Oh, now you have the number, 328, oh, are these significant? Well, there's a decimal point, so yes, they are. Huh? At least more sense than what I was, though. Good. And so if I give you this, three, two, eight, 0.00, Seven? Yep, that has seven significant figures. They're all significant. These zeros after the number are significant fly, because there's a decimal. I don't care if they comes backwards. If there's a decimal anywhere, it's going to be significant. Okay. 06 significant? Yep, this is a decimal. Any questions about significant figures? Yes. Nathan, how is, uh, two zeros, like, after, having that significant?C's a desk. Remember what I said? It doesn't matter where the desperate point is. If the zero, after the number, there's a decimal point anywhere in the number, they're significant. Alright. Okay. I think that's much simpler. You know, to count numbers, we know zeros between numbers are only significant. Now you know zeros before numbers are never gonna be significant. It's zeroes after the numbers. They're not significant unless there's a decimal point than they are. Any questions about that? All right, we have here. Uh... All right. Um... All right. This is what I'm going to do. Good news for you all. Next time we get together on Tuesday, I'm gonna have to end classes, I think. Next time we get together on Tuesday, you're gonna have your first place. Now, it's not gonna be bad, 'cause it's only on the stuff we went over so far, all right? We haven't done anything mathematical stuff. Odds are, when you build next time, then you'll get another, but, um, the next one should be pretty straightforward. It's going to be on things such as, like, mixtures, substances, physical, chemical changes, properties.
The scientific method involves: Question → Background Research → Hypothesis Construction → Experiment Testing → Results Analysis → Conclusion. If the hypothesis is valid, results are reported; if invalid, revisions and retests occur. Key concepts include:
Objectivity: Essential for impartiality; consensus is excluded from the method.
Terms:
Matter: Has mass and occupies space.
Element: Cannot be broken down further.
Atom: The smallest particle of an element.
Molecule: Composed of two or more atoms.
Composition: Specifies which atoms are present and their quantities.
An illustration includes how the original hypothesis about vitamin A preventing rickets changed to discovering it was vitamin D through experiments.
Properties: Physical properties, such as color and boiling point, can be observed without changing the composition; chemical properties, like flammability and reactivity, require a change in composition.
Changes: Physical changes, such as boiling water, leave composition unchanged, while chemical changes, like burning paper, alter it.
Because this leads to a law, a law of... mass. Conservation. Okay. And that's this, mass... is... either... created or destroyed. And... a... a chemical. Oh, yeah. All right, so that came from a lot of what Lavoisier was doing. The law of conservation of mass. So if, for example, if you burn alcohol, you have C2, age 5, OH. What happens there is that is going to react with oxygen. That's a combustion reaction is. So that just reacts with oxygen, and it produces carbon dioxide, and water. Now, what happens is, if you weigh out your... your alcohol is 4.607 grams, that will react with 9.600 grams of oxygen. It will produce 8.802 grams carbon dioxide, and 5.405 grams of water. Hence, 14.207 grams of reactant on this side ends up producing 14.207 grams of product on that side. Mass gets conserved. Any questions on the law of mass conservation? All right. How we doing? All right, We can do this. Um... Uh... Next on our list. Joseph Kraust. Now. He, um... did some experiments and came up with something called a law. I'm definite. proportions. Okay. Said this, Different. Samples. of... a pure... chemical substance. Always contained... Same proportion. Of elements. My mass. So... if you take something such as water, if you get pure water from the ocean, if you get pure water from rain, if you get pure water out of a river, okay? All pure water. contains... one part, hydrogen, and 7.9 parts. Oxygen. By mass. Now, for those of you asking why by mask, doesn't that make it more complicated? The answer's actually simple and straightforward, because this happened a long time ago. Back then, they were putting laboratories with ways of measuring mass, but not ways of measuring how many atoms something had. And so what they found was the proportions by mask, 'cause that's what one thing they think measured, right? So, water, no matter where it comes from, if it's pure, will always contain one part hydrogen, 7.9 parts oxygen by mass. That's the law of definite proportions. Okay. Oh, my God. Uh... Let's see. da So, uh... Yeah. Yeah, we gotta go to Dalton's atomic theory, I think. I think I'll do that over here. Unfortunately, it's a lot of writing. You can kind of force you to script things down. But keep in mind, I have my electricals posted, but you've got to look at that. Ugh, here. Here we go. All right. All right. Then came Dalton, John Dalton, who came up with Dalton's... Atomic. Theory. Okay. in which he was much more specific with how Adam sort of worked. All right, Dalton County Theory had four different parts of them. And, yeah, unfortunately, we do have an adult atomic there. First part is elements... are made. tiny particles. Call... Adams. Okay, so that those are the particles that make up elements. Second part. Adams, of the same element. They have the same... Mass. Oh, no. Atoms of different elements. Have different masses. So this is a way of distinguishing how one type of atom was different from another. Let's say the difference between gold and silver. The difference between gold atoms and silver atoms were all gold atoms, had the same mass, and all silver atoms, had a different mass. They were all the same, but they were different from the massive gold atoms. And that's how you could tell them apart, and that's how they were different. Third part, chemical combinations. Um, elements. To make different substances. Occur. When Adams... join together... in small... whole number. Are you sure you can? Ratio. Okay. This described how new substances get formed from atoms, all right? They don't just pack together haphazardly any old way. They tend to form these different substances by joining in small, whole number ratios. So when carbon and oxygen get together, they'll make carbon dioxide, for example, CO2. They won't make something like C, 147, 0, 358. They won't make stuff like that, all right? They will make a small, hull, number ratio combinations. All right. And the fourth one. Space for food. Hope you can see this. All chemical reactions. Only... rearrange. The way... atoms... are combined. Adams. And... either be created... nor destroyed. Okay, so if you observe a chemical reaction, no matter how violent it looks like, like explosions, you're not destroying any atoms. You're not creating it. All you're doing is taking the atoms that are already there, and you're rearranging them to make new substances.