hey so we're going to be talking about measurements that are common in introductory chemistry a chem 101 course and their Associated units okay we're just going to keep this uh nice and simple we got four things we'll be talking about today we'll be talking about length and we'll be talking about volume volume is the third dimension of length and then we have mass and then we have temperature one more thing we'll talk about is we're going to sneak in a discussion relating mass and volume together and we're going to call that density all right so first up uh we have length all right so length is just a measure of distance going from one point to another we are in one dimension all right common units just to refresh you uh we could be working in the metric system meters centimeters millimeters uh we could be working uh with these sorts of units um for longer uh distances maybe uh something like kilom uh or miles okay so um one thing I'm going to be doing the side uh between each examples I'm going to be showing how we progress to three dimensions right now we are in one dimension we're measuring length and um we have 10 uh centimeters that I drew out here all right we're going to go to two Dimensions now and we're going to be talking about uh area Okay area Works in planes or sheets uh very much like this piece of paper so we are in two Dimensions now all right common units I just wrote the same things except with squares on all of them like square meters square feet uh things of that nature okay so I had those uh 10 cm from uh before right and now we're going to take it into two Dimensions so we have 10 by 10 here we don't write 10 cm squared it's 10 * 10 so it's 100 cm squared okay all right now we're going to move into uh three dimensions okay so we can have a units such as these um I guess if you really wanted to you could measure stuff in like a cubic kilometers or uh cubic miles maybe if you're like measuring the amount of gases in the atmosphere I don't know okay uh but we're working in three dimensions now all right now this is where I can show a nice cool little prop right here I have can I F in the screen maybe I'll back this up a little bit all right this is a 10 by 10 x 10 uh Cube okay block all right you can see one two three 10 10 going that way and then 10 uh going along with the height I'll flip that show it to you okay there's something uh special about this block uh this block is 1,000 um cubic centimeters all right write that down okay this is 1,000 cubic cmet we got that volume from doing 10 * 10 um by 10 to get that um 1,00 all right and what's special about this block is that uh these uh 1,000 cubic cenm all of this is equal to another unit of volume that we call liters this is a one liter all right so I'm going to show uh the significance of one liter um you may be used to liters U more in the sense of like uh drinking a beverage you get a liter bottle or like a 2 lit bottle um and maybe reminds you I am a chemist I'm G bring out glasswar um you know we would maybe have a container like this for that looks better uh measuring out um fluid okay um but liter cubic centimeters any volume unit will work for any phase of matter whether it's solid liquid or gas okay so back to the lader though I want to show an interesting uh relationship we um just said that a uh 1,00 cubic cenim is the same as a liter all right now the Millie prefix means 1,000th of something so if we have one liter there's going to be 1,000 milliliters in it well both of these quantities the 1,000 cubic centim the th000 milliliters are equal to 1 liter we can set them equal to each other and uh we'll get a relationship like this if we were to cancel out the 1,000 on both sides we would see that 1 cubic cimer is exactly the same as 1 milliliter okay that's a useful thing to knowe because sometimes uh with volumes uh you'll see them written one way or the other it's actually um perfectly interchangeable with each other all right one thing I do want to know I'll put it on this poit note is if you're going to change out the unit if for some reason you wanted to write a milliliter instead of a cubic centimeter uh you would have to just go from there to there what I mean by that is you cannot write something like that milliliters okay is already a three-dimensional unit it's already in three dimensions and so you don't write a cube on it like you do with cubic centimeters okay since centimeters is a one-dimensional unit you turn it into three dimensions with that three over there you don't do that with the milliliter so this um is wrong okay let's just not do that that would be like the ninth Dimension and I'll leave that for like theoretical physics and mathematicians uh to figure out okay don't write um a three over there another thing that I've seen um people kind of get crossed up with is uh may be thinking how is it that I have a CTI prefix here and I have a Milly prefix here okay I think the easiest explanation for that is that's just the way the equivalence of went you can clearly see here going back to this block I have one centimeter here there there and we go 10 by 10 by 10 and it's a th all right and it's 1,00 cubic cenm and yet if this is called one liter there should be a, Millers in it so it's just that's just kind of the way it works out that um we happen to have two different prefixes here okay don't mess with them you can't change this to like an M you can't change that to a c that would ruin the equivalency as well right so we'll just uh stick with this factoid okay let me pull this up so that you can see this in good detail one cubic centimeter is the same as one milliliter all right uh the next unit I want to talk about is uh Mass okay and mass is where um I have to maybe start getting a little bit more uh precise or careful uh with my explanations um I think mass is something that uh we can uh relate with okay we we think of mass and we think of oh that's like stuff right um and that will turn out to be my favorite definition but we can maybe get more uh technical uh than that um but uh first let's introduce um some common units okay uh um kilograms grams milligrams uh micrograms all right um those in nutrition fields or maybe some other field maybe like water qual maybe they'll see like a MC that is lowercase okay uh later on you're going to see atomic mass units as you can tell with this uh power of 10 this is a really dinky number we use atomic mass units when we're talking about the sizes or excuse me the masses of like protons or uh neutrons all right when we're talking about the masses of like single atoms and Isotopes all right so oops I revealed too much too late oh whatever I'll just keep on the video so um I want to show some different uh definitions of masses so it's not just in my words all right um going to the Miriam Webster dictionary first um you can read uh through that some things that kind of stick out uh at me is it pays attention um or it mentions like the amount of material okay so we associate Mass with like how much uh material there is how much uh stuff if we want to get really technical it has this word inertia okay it's a property of a body of matter that um is a measure of its inertia so inertia is being uh taken into account so just to kind of refresh um or Define what inertia is inertia is uh the resistance to movement okay um and so in order to move something uh you have to push it or you have to pull it and and in physics terms we uh we call that a force now this isn't a physics class so I'm not going to write hopefully too many equations would I put this equation on one of my chem 101 exams uh I would not um but this is um force is equal to mass okay here's that word again Mass um times uh acceleration that acceleration is just um uh you know uh how how how much you're changing the speed of something okay so that could be an acceleration you apply like you're throwing a baseball or uh we could just be talking about the acceleration um like due to gravity then we would uh find um the acceleration due to gravity you can look it up but um uh that's around 9.8 meters per uh second squared um on Earth here I'll write that I know someone wants to write that down since I said it um and um but that's a force okay so uh basically we want to to be really technical with the definition of a mass it's the property of matter where uh the more of this Mass property you have uh the more difficult um it's going to be to push or pull it to move it in other words you're going to need more Force so if this mass number goes up um assuming the acceleration numberers equal uh so is that okay so in plain speak to keep it really simple uh the more massive an object is uh the harder it is to push or pull it harder it is to move it and that that is um the definition all right um we can go to the National um Institutes of uh Science and Technology standards and techn I think it's standards oh my gosh I'm a scientist I forget what it stands for whatever um so uh and they they get at uh very um similar ideas inertial property oops um the amount of matter it contains or a matter okay so um I'm I invite you to come up with your own definition all right U my favorite definition to keep it really simple it's stuff all right so now let's talk density so density relates mass and volume together it's the amount of mass that you have in um a certain volume so you you can write a density equation like d equals m over V all right um just so that people know others might use a lowercase D others might use the Greek letter row okay but uh I think I'm usually going to be uh sticking with this but it's Mass uh over volume so mass is going to depend on um what elements are present in your material okay so you'd have to go to a periodic table to get a general sense of that I'm not going to be talking about that uh a ton today but just to kind of give you a preview for the future here okay we can go to a periodic table and it's going to um have something to deal with these uh bottom numbers so we go to aluminum or uh shall I say aluminium all right um 26.98 about 27 all right and then we can go to something like tungsten uh 183.0 4 so if we were going to compare aluminum versus tungsten we can see that comparing one atom of aluminum to one atom of tungsten um tungsten is going to be a lot more massive all right it would be uh heavier if we were measuring um its weight all right and um I picked those two because I actually have those two uh elements handy I have two cubic inches of aluminum and a Tungsten you can see they're both the same volume a cubic inch but let's just listen to their difference in density even dented my paper all right so uh you get the uh idea all right so tungsten uh appears to be sounds like a more massive uh element okay um and um but it's not just about the um mass of the individual elements I mean sure tungsten is more massive we saw that in a periodic table has a higher um atomic mass number but um it's ultimately about how tightly you pack your stuff into the volume even if you have a heavy objects if they're spread out in um your sample then it's not going to be as dense as it could be so how tightly can we pack a material okay um in the chemistry class that's going to have to deal with the distance uh between atoms we don't talk about that too much in a chem 101 course maybe a tiny bit later on um as well as a packing efficiency how closely you pack uh the atoms together and um that can be studied in terms of a material's uh crystal structure so without any math I just want to kind of show how density uh plays out the at the atomic level I'll bring out um these little spheres here all right so I have four of these red spheres all right if I arrange them in kind of like a perfect square here it may look like neat and nicely uh arranged o there we go um but I would argue that this is uh not the most uh efficient way to pack in fact you can see like this large gap here if I just slide things over you can see those gaps get get way smaller all right and so uh filling the Gap staggering them is the most uh efficient way way uh the pack matter okay but that's only one layer okay we live in a three-dimensional world all right so um I could put maybe the next sphere here and sometimes nature will do that but often what nature will prefer is to just oops let things slide to the Natural uh middle okay we see that we have a gap for things to sit in okay whereas here uh there is no Gap so some materials sometimes you'll see like that direct a stacking on top of each other but um often for some other materials uh you're just going to pack things um as closely uh as possible so um but that's going to depend element from element so that's what I'm talking about in terms of the packing efficiency uh crystal structure if that in if that interests you I'd be happy to make another video or two on that um just uh let me know but uh that's the uh idea of density relating mass and volume together here we go all right and then the last measurement I want to talk about uh for this video think we're just doing a quick little overview of a bunch of uh measurements is temperature okay so common units for a temperature okay um I'm in the United States so uh weather is often done in Fahrenheit but for most of the world uh um it's going to be uh Celsius all right and then uh we have this Kelvin scale which people may not be uh as uh familiar with all right um there are mathematical ways to relate these okay I'll write them in case you're curious you can skip this over if you're like I'll wait till later um the Fahrenheit temperature is going to be uh 1.8 times the um Celsius temperature plus uh 32 all right um some people like to write this in a fractional form so 1.8 is also known as 9 fths and you can go that way all right and then um to go between Celsius and Kelvin you're going to add 273 um to the Celsius uh temperature if you want to be really spoton um you have a high resolution way of collecting temperature data uh 0.15 um is actually the complete constant um so uh temperature uh some closing thoughts um we associate temperature with thermometers with the weather um but what does it really mean okay uh I like to think of temperature as um the strength of movement uh in um a material okay um so let me um maybe bring up some other definition so you can maybe get around that idea we'll start with the mirium Webster okay they are calling it a degree of hotness or coldness um measured on a definite scale okay uh nist gets a little bit um more specific uh how much average energy of motion okay so we're talking about movement kinetic energy um something's atoms um or molecules have okay I like to think of uh this in my definition I like to actually talk I I like to use this word uh strength when I'm talking about temperature um the strength of the motion okay because what I get scared with is people confusing a temperature versus uh heat um or more uh accurately uh thermal energy okay um so let me just write this here as a closing thought temperature is not the same thing as uh thermal energy okay we'll just call that heat in quotations if you're wondering why it's in quotations I invite you to go on a Wikipedia Rabbit Hole or something and check that out I'll maybe discuss that in another video but heat all right they're they're not the same thing all right they're not the same thing temperature like I said is the strength of the motions and something so uh you have a fire fire is very hot okay um you're going to have a higher temperature um a common question that's posed is what has uh more thermal energy what has more heat um uh lighting um a match okay uh versus an Olympic uh swimming pool okay which one has uh more heat okay so let you think about that a minute you can pause this all right so the answer is going to be the swimming pool the swimming pool has um more heat it has um it's way bigger it has overall more vibrational energy but if we're talking about uh the strength of the vibrations they're not as strong as what's happening in the match the match tip you have your atoms moving way faster stronger thermal energy compared to the lower temperature of the swimming pool okay so hopefully that helps elucidate uh the difference between those two all right those are the four main measurements we'll do in a chem one chem 101 course um if there's a little other ones later on we'll talk about those but those are going to be the sort of measurements and therefore the sort of units you're going to be seeing very often in this course all right hope that helps thanks and take care