hello so our first Topic in chemistry is going to be um the study of matter which is really what chemistry is but we'll get to that but our first chapter is matter and measurement okay and so let's talk just a little bit about what chemistry really is and chemistry is considered to be the study of matter so then you think about okay what is matter so matter is anything that has mass and occupies space which means it has volume which means that you can actually we um contain it weigh it and study it okay so that's kind of what matter is chemistry is a really very old science and whether you were called a chemist or not it didn't matter people were still studying chemistry and uh eventually the name came out to be chemistry it started with Alchemy and it came eventually became chemistry as in about 300 years ago uh but otherwise you will see that in history a lot of things were based on chemistry so the an age Bronze Age for example medicine is all based on chemistry when um fire was invented fire is nothing but chemistry and then painting everything is chemistry for you also uh from morning to night everything is about chemistry right you get up in the morning you brush your teeth uh take a shower hopefully um you know use soap shampoo whatever it is and then you know you have breakfast so whatever you eat is chemicals good chemical bad chemicals right but still chemicals and then you know your phone is a chemical computer is a chemical everything is chemistry so really chemistry is a study about everything um chemistry was studied as one subject uh kind of like a one thing and then it grew out so much it grew so much that it had to be divided into different parts and so there are about three or four major parts to chemistry organic inorganic and physical and then eventually uh analytical came about last century and then biochemistry and now there is even more with nuclear carbohydrates uh protein chemistry there is so much more so there's lots to do in chemistry okay essentially every kind of field has some sort of chemistry in it even something as simple as having an aquarium okay it's going to have chemistry in it so baking has chemistry in it so it's just said everything is about chemistry um what we do in chemistry as far as general chemistry is concerned is going to be a lot of inorganic and a lot of physical okay there's going to be some Analytical in there but we hardly do any organic or biochemistry or anything okay so um remember this is the first first level of chemistry so we don't really go a whole lot of deep into things we'll talk about some of the fundamentals how to write equations how to do simple calculations learn about atomic structures so not a whole lot okay all right so before I really get into what chemistry really is and what we're going to do in this chapter I want to talk to you a little bit about the scientific method and the scientific method is something that a process that all scientists follow and what this is is a very systematic way of doing science so that your science is actually considered to be good science and not junk science or pseudo science um so you want your science to be good and that's why you know sometimes we expect too much from our scientists because we know that they are thorough okay so what is that thoroughness where is that coming from so here it is okay there are five key things that we do and there could be more of course uh but it's in in in hidden in there so first of all is of course your observation observation comes from Curiosity also but observation is really the key here if you're not observing anything then really you're just living your life daytoday just like that okay so um you know you observe things okay today the weather is like this or today you know my garden is blooming things like that those are observations even though very broad but still there are observations so you have to observe something in order to start something of a study okay then you come up with a hypothesis thinking that okay maybe this is happening because of this all right cuz if you don't observe something you're not even going to think about that right so hypothesis is something that you develop and then if you want to study that further then you have to do experimentation which means you devise a method by which you can study something now experimentation is generally like the biggest part of any any science because this is where you have to um you know study something it might take one year 2 years 5 years uh a day it depends on what kind of study you have all right and so experimentation can take a lot of time or not enough but this is where you collect data also all right so there's not of numbers involved here so experimentation is the biggest thing and here what you do you first of all you collect data right and then the second thing you have to do is you have verify your data how do you do that to verify your data you have to repeat your experiment so you kind of duplicate it yourself okay can I do this again and if you can't well then you go back and do something right and you change something in there and try it again and then try to duplicate that once you have done your experiment twice or Thrice and you're like okay I get this now this is working then you take it to your peers and then they have to do this experiment and make sure it works because if it doesn't work by them then you're like okay you know we didn't do this properly or we missed something all right so then you get it back as approved or no it needs work okay kind of a thing so that's experimentation once you do that and by the way this is where you publish papers into the you know research journals and whatnot then you come up with a theory like okay I think I got this now and I think this Theory now is going to verify my hypothesis because this is what I was thinking that this is happening because of that so the theory now is going to validate that so does it follow your hypothesis if it follows your hypothesis great okay if it doesn't well that's fine too right because you had a hypothesis and now you found out something else and that happens in science a lot that you know you try to propose something it doesn't work out that's okay you just go back to the board and you start over again then finally the theory has been verified again and again then it becomes a law okay and the law is like the law of the land okay like this is it like the law of gravity this is what happens now these two things the theory and the law is pretty much like a done deal this happens especially like the law is like big time but even Theory it happens after a lot of testing and whatnot so it's it's pretty much a standard thing like this is what's going to happen so to challenge these two which you can challenge these two so but to challenge this you have to propose your own hypothesis and then you have to do experimentation okay in order to prove that but you can okay so that's not a problem but anyhow this is a scientific method this is what all scientists will follow we may not talk about all these things independently but we do all of this okay one way or another so let's talk about matter because we started with saying that chemistry is a study of matter so what is matter and matter has anything that has mass and volume right we talked about that so then matter first of all will classify in the next few slides what matter is so the first classification we want to do is of course the three phases which really is very Elementary and I think you probably already know this so solid liquid gas and gas the molecules are really far away from each other liquid the molecules are closer solid the molecules are very close together they're kind of packed together you can take any solid and uh put it into any shape you want to liquids take the shape of the container gases forget it no controlling gases okay they'll be going everywhere so um that's one of the classification of matter then let's talk about another classification of matter okay so here is a nice chart I'm just going to follow this chart you can read all of this yourself so here is matter matter can be classified into two things okay so mixture and substance so mixture as the name says it's a mixture of something okay so what like two or more things okay substance on the other hand is just one thing all right so first let's talk about mixture so mixture is also of two different kind of things so one is a homogeneous mixture the other one is a heterogeneous mixture a homogeneous mixture is something that is uniform looking which means you can't tell it that you know or tell it apart so if you look at a glass of water for example coming from your tab you can't tell that there is a mixture so you really have to do some study on it in order to figure out that you have something mixed in there and that happens you know and people don't know that there might be something dissolved in that water so uh it's a problem okay when you have a homogeneous sub uh mixture homogeneous mixture can also look like a substance right cuz you might think oh it's only one thing so it can be a little bit of a problem okay but homogeneous mixtures can be solids liquid or gases like the gas in front of you right now the air atmosphere it's homogeneous you cannot tell that it's a mixture of four or five gases heterogeneous mixtures on the other hand they are you know something you can tell you know easily that okay it's a mixture of things so for example if you had you know soup for example okay Minon soup not tomato soup but uh ministr soup for example or a salad you can tell that there are different components to it so that's called a heterogeneous mixture so you can easily tell okay I got a mixture so matter then on the other hand it can also be substance okay and that substance can also be then divided into two an element or a compound element exists by itself so for example if you're talking about gold gold can exist by itself when you take gold and you combine it with something then it becomes a compound now compound can look like an element ment also okay and so you have to know you have to study a little bit more so sometimes you know when scientists find something in nature then you have to do analytical studies on it to figure out if it is a a a mixture first of all or is it an element is it a compound because sometimes you can't really tell okay unless it's something like you know um you can tell like a rock that you pick up which has lot of striations on it then you're like yeah okay it's a mixture and could be a compound so then you can figure it out otherwise you have to do a lot of analytical studies okay on this so element on the other hand it exists by itself so let I said gold iron silver neon you know any of the um gases here helium they can exist by themselves at this time I will ask you how to differentiate between all of these but again I will give you things only that you know okay I will not give you something that you don't know yet okay all right so one last thing on this slide that I want to mention here is about mixture going to substance and that over here you can see that it can be separated by a physical process so for example if you wanted to wash your salad you can absolutely do that okay or if you wanted to take tomatoes out of your salad you can do that all right so just pick out the tomatoes or if you don't like onions you pick it out so that is a physical separation you're not changing the onion in any way all right so so that's a physical process so you can take a mixture and you can actually separate a mixture using physical processes into substance and by the way just so you know this is a big big big portion of chemistry is separation chemistry is how to separate things out you know into different uh substances okay so here is just uh some examples of how to classify matter so here this is whether something is a matter or not and these are just something that came to my mind you know okay so iron for example is matter uh human mind is not a matter mind is a very abstract thing so you can say yeah it matters but it matters but it's not matter okay so exhaust fumes yes you can see them you can contain them and that's matter okay so so on and so forth and then here you you can see some examples here for um homogeneous and heterogeneous so helium gas for example is going to be homogeneous because there's nothing else in there um a cup of water from the beach oh yes and if you've gone to those Floridian beaches you know it's heterogeneous okay and there's stuff mixed in it so again I will give you things that you should be able to classify okay one way or another so let's talk a little bit about properties of matters okay cuz we're still in matter right we're still discussing matter so uh let's keep on the left column first so properties of matter first of all physical properties and chemical properties so so there are two kinds of properties that we study in chemistry physical property would be something like what is the color of a material does it conduct electricity does it conduct heat so it doesn't really change the chemical identity of the uh substance you're trying to study chemical property on the other hand will study that I mean a lot of chemistry is both of them but chemical property is a lot of it okay because there's a lot of reactions going on now so how does it react with water or acid or anything like that okay so if it changes then you know that would be like studying a chemical property all right then we also can have changes in the matter so a physical change in the matter does not change the chemical itself as I was saying when you separate out a heterogeneous substance you know like salad mixture you remove tomato you're just removing it you're not cooking it you're not changing anything in it so that's a physical change kind of thing okay or that's a physical separation but the physical change would be like going from um ice to water you can take that I uh water and freeze it right back into ice and it's not a problem it is still water so melting for example right that process there is what we say a physical process where you're just changing the phase of something like that so a physical change does not necessarily then change the substance itself chemical change on the other hand uh is irreversible okay so which means that when you do some chemical change then you cannot get your chemical back all right so some simple examples would be like boiling an egg so when you boil an egg everything is changed okay where it was a liquidy uh thing before and now it's not liquid anymore now it's all solid okay so a chemical change has occurred you can uh boil rice also for example or cook vegetables any of that kind of thing and I know I'm talking about cooking but you know it's the is the thing that everybody does pretty much and so when you do that you cannot go back to the original thing and that is a chemical change then okay so physical change you can it's you can go back it's reversible chemical it's not and that is how I view the chemical property and physical property also okay that is it can you take it back or is it done you know is it reversible or not that's how I think about it so here are some examples for um all of these and so um the ability to uh burn gas and if you're burning something then it's a reaction okay so that's a chemical thing diamond is hard and that would be a physical thing for example okay you can see the rest yourself and then physical change chemical change all you need to do in this one it say is it reversible or is it not reversible so when you think about mining mining is a whole chemical process where you're taking something from um you know a mixture of thing or a compound of thing into a pure thing so iron oxide going to iron so that would be a chemical change when you take wool and you spin it into a yarn that's a physical thing you can take yarn and take it back to wool again you just have to have the process for it we just don't do it that much that's why we don't think about it okay but otherwise you can actually go back all right so think about those things when you are trying to uh think about chemical or physical change again reversible or not reversible okay all right so now let's look at um a little bit about data okay we're going to talk a lot about data in the in the next portion also but I just want to kind of introduce some things here to you so data is collected in different ways so there's a quantitative data and there's qualitative data quantitative quantity meaning that you can measure something which means you're dealing with numbers okay with quantitative things so whenever you have anything that's collected in ctim millimeters or this many pounds or this much it took this much time that's quantitative when you're looking at a qualitative data then you're just looking at some physical properties you're not really kind of well you are you know physical properties can be measured too but in qualitative you're looking at the quality of something okay so what's the phase solid liquid what's the color uh quality you know and just kind of getting an idea of something it's not really um measurable how is that so when you're looking at a color for example you might see blue somebody else might say blue green you know something like that so that's a qualitative uh quality thing so that's qualitative data then you can also classify those properties as extensive properties or intensive properties okay and an extensive property depends on the amount of matter you have so the amount of matter meaning that if you change the mass of something then that mass is going to be an extensive property because now you have more of it and as soon as you have more of something that is the amount so that change the mass that will change the volume so that's an extensive property intensive property does not depend on the amount so if you take boiling point of something um it's it's an intensive property whether you take the boiling point of uh 100 millit of something or 1,000 mlit of something it's not going to matter okay so intensive is you can think of it as you know this is who I am kind of a thing because yeah this is who the substance is okay so the density of a substance you know something like that so some of these qualities these are intensive they don't change with how much substance you have in there okay okay so here are some examples of qualitative and quantitative data since the answers are all given there um it's kind of easy for you to see I hope uh what everything is so separating color uh separating Socks by their color that would be a qualitative thing okay because this is just kind of like very uh subjective kind of a thing so that's qualitative if you're measuring the temperature of something that's quantitative okay so again remember numbers wherever there is number that's quantitative so then extensive and intensive properties is uh extensive again remember depends on how much you have extensive intensive within coming from within itself so if you're adding water to something okay then means it's going to be extensive cuz you're adding some Mass okay to something like that if you're measuring the temperature of evaporating alcohol so whether the alcohol is 100 ml or 200 Mill does not matter it is still the temperature and it's going to be the same and that's intensive okay so uh go through all these examples uh and hopefully you will understand uh where we're coming from okay so uh that brings us to the end of the first portion and so here we learned a little bit about matter and some properties chemical physical intensive and all of that wonderful stuff okay on to the next one okay in whenever you ready