hello my dear students welcome to the amazing amazing platform of PW English I am bhavika your Chemistry Mentor welcoming you to the our next lecture of basics of chemistry and that is hm element and compound okay we started this series with the motive to make strong your Basics your foundation okay in order to build a strong building its pillars should be strong it should be firm so let us make your form your foundations strong in order to make a bright and strong career okay so their topic today is element atom and compound many students get confused in it that what is attempt is element what is compound they just get confused in it sometimes they think that H2 is atom or relevant sometimes they think it is an element sometimes they think it is a mixture sometimes they think it's a compound okay so it's not your problem it's this problem of many students so I thought to took up this topic as my next lecture okay so let us just dive into it okay so first of all what is atom C uh you might get confused between element and compound but you will never get confused between atom and element because a atom is a single entity right an atom is an atom it is an entity which consists of a nucleus in between okay it has a nucleus in between which consists of proton and neutron and it has electron moving around it okay so it's just a simply a single atom when I'm talking about but but when I am talking about molecule okay when I talk about molecule it consists of two or more atoms okay when I say molecule it consists of two or more atoms not necessarily those atoms are same or different same atoms means hydrogen and hydrogen are same atom right helium and helium are same atom but if I talk about hydrogen and helium they both are different atom how different because both consist of different number of uh electrons different number of protons different number of neutrons like their properties are different okay so all the 118 elements you see in periodic table all are different all 118 atoms are different okay when you talk about for example calcium element okay when you talk about calcium as a element then it means it consists of the atoms which are which are of calcium only all the atoms are of calcium right and that atom become a element okay so for now we we are going to talk about element more but for now you can think as one atom is atom but two or more same or different doesn't matter two or more atom is for example H2 H2 is a molecule HCL is a molecule right so those type of entities are molecule okay so first of all we have to just see this basic classification right we must go through this basic classification one C we have a matter right matter is anything which has mass and occupy space right matter is that substance it is that thing which has mass and its occupy space which means it has volume right I am a matter because I have some mass and I am occupying some volume over here okay so that is that is matter so uh C matter is divided into two part one is pure substance and one is mixed pure is it is made up of only one type of substance see the pure term which we use in our day to day life is different than the pure term we use in our chemistry okay so don't get confused we often say like it's a pure milk pure oil pure ghee okay these are the things we use for uh for Pure in our day to day life okay which our Pure means it does not has any impurities but pure in the chemistry means it has a one type of substance okay it has just one type of substance entirely that type of substance okay and in when it has more than one type of substance then you can say it is a mixture okay fine if I talk about pure Subs it is again divided into two and here it is our key point to learn pay attention over here one is element and other race compound now what is element means that molecule you know now what is molecule yes that molecule which consists of same type of atom okay just like H2 O2 N2 O3 S8 what are they they are elements yes they have more than one items but which type of atom same type of atom right same type of atom more than one that is your okay very easy next is compound compound is also molecule listen yeah sorry compound is also molecule in elementism also molecule see what we studied in the definition of molecule anything which has more than two or more than two atoms right two or more than two then if I talk about C here if I have to write the example then here example will be here example will be H2 right O2 but if I write example over here then HCL H2O NH3 yes different type of atom and here same type of it if all these are molecules all these are molecules but one which has same type of atom their element and here C H is a different atom yes CL is a different atom of course their properties are very different they consist a different number of proton electron and neutron yes different type of atoms so compound right H2O is also compound NH3 is also compound so again here one confusing point is uh okay ma'am we understood that more than two two or more than two type of atom is engaged different type of atom is engaged then it is compound then what is the difference between mixture and compound that we will see okay see if you talk about matter more than one type of substance is present that is mixture now you will see my different type of item is present in compound also and different type of atom is present in mixture also then what is the difference between mixture and compound here compound is went to a different type of atoms are in definite composition if you see water then you will always find you may take water from any Source water will always have two atom of hydrogen and one atom of oxygen but in mixture there is no definite composition okay if I make lemonado you make lemonado your mom make lemonado all three will have different taste because we have added different amount of salt sugar water and lemon there is no standardized process for this are you getting my point or not okay there is no standardized process for making lemonado so that becomes a mixture air is a mixture okay no definite composition but if it has definite composition then it become compound okay please see the entire table once again okay picture can also be distinguished into two homogeneous and heterogeneous homogeneous means uniform confirm composition and heterogeneous is irregular composition for example homogeneous composition means lemonade okay the sugar water lemon and salt as mixed with each other so uniformly that you cannot see their boundaries can you see salt in lemonade okay okay here is the salt here is the sugar here's the lemon can you see like that no because it is uniformly mixed with each other right but for heterogeneous you can clearly see if you see the mixture of oil and water you will see two different layers floating over each other because they do not uniformly mix you can see uh the mixture of sand and water right you will see that sand just deposits in the end of the container yes it will just uh sink at the bottom of the container it will not mix so those type of mixtures are known as heterogeneous fixture clear till here see now we'll talk about more about elements okay Robert Boyle okay Robert boy was the first scientist to use the term element okay Discovery and using the word is two different thing don't get confused in it see Robert Boyle was the first scientist to use the term element okay he used the term element and Laurent levioser levisor a French chemist was the first to establish an experimentally useful definition of an element he was the one who gave the definition of Parliament levisor and who coined the term if they ask you who coined the term then Robert Boyle was the one who coined the term okay two different things he defined that element as a basic form of matter that cannot be broken down into simpler substances by chemical reaction of course you cannot make it more simpler because it is already in its simplest form okay it is already in is it in its simplest form elements can be normally divided into metals non-metals and metalloids if you want to further classify elements okay if you further want to classify elements you can classify them as metals non-metals and materials so that's how elements are they are formed from same type of atom they cannot be uh they cannot be divided into any simpler means okay they are already into their simple composition they cannot be broken down into simpler substances by chemical reaction okay okay so this is a pictorial representation of what I'm trying to tell you okay so this is this is an element okay this wall is an element and this red bricks okay this red bricks are atoms okay you see all the bricks are of same color all the bricks are of red color okay so this is a example of element where it is the ball is made up of same color of bricks that is red bricks no other color okay no other color let me write over here same atoms that is same color bricks clear till here yes so this is a pictorial represent representation what of what I'm trying to tell you next are compounds okay I hope you have understood elements now let us go forward to compounds elements react to form a new compound okay it form a new compounds elements react with each other and they form new compounds the composition of each new substance is always fix the new substance is totally different proper piece yes it may or may not have different properties most of the time it has different properties the constituent can be separated only by chemical or electrode electrochemical reactions let us see example for that if you take any and cl2 if you react to them both what you get NaCl and if you just balance this reaction this is the thing now if you see dear students sodium is a highly reactive metal okay it is a highly reactive metal this is a poisonous gas this is a poisonous gas and if you mix them both what you are getting common salt the one which we are eating every day in our food so you see you see the analogy the the properties has drastically changed yes properties has drastically changed L2 can be a poisonous gas sodium is a very reactive metal if it gets in contact with a little a one drop of water also it burns rapidly okay it has to be stored in kerosene yes we usually store sodium and potassium in kerosene because they are very much reactive in air in water both but when it reacts with cl2 and forms NaCl it come up with her totally new different properties and yes this can be broken into simpler substance elements were not be able to Broken birth yes you can break this and you can get your elements okay okay they are always combined in a definite composition okay so this is the thing for compounds see this represent compound here there are two different types C one is marooned color and one is red two different atoms that is two different color bricks see there are two different colored bricks so two different type of atom that is compound okay in a definite composition right so this is a example this is a pictorial representation of a compound foreign that was element you may ask me man also tell us what is mixture because there is some confusion the compound and mixture are so alike right so elements or compounds just mix together to form a mixture and no new compound is formed see the thing new is forming if you are adding adding salt to water okay if you are adding salt to water what will happen the water becomes salty so did you get a new compound no this salt tasted salty before addition also and after addition to water it's it tasted salty yes see salt plus water it gives you salty water yes so here salt toast tasted salty here the water also tasted salty so do you see any difference nothing no difference ma'am it is the same so that is what I'm trying to tell that no new compound is formed it has a variable composition okay if you make salt water and I make salt water it could be different I have added one teaspoon you must have added two teaspoon okay your brother or sister must have added three teaspoon right so it it differs there is no standardized process okay a mixture shows the properties of the totally different constituent substance okay it has their own properties they do not adapt the constituents can be separated only fairly easily by physical methods okay salty water if you want to again extract salt from it then you can use distillation yes a one of physical method okay you can just heat it in the summer so what will happen water will get evaporated and the salt will left behind so to a break compound we needed a chemical method but two separate mixture we can also do it by physical methods okay so this is the pictorial representation of mixture okay see there is a white colored green colored yellow red this one is maroon this one is green okay different type of different type of atoms that is different color of critique okay this has a variable composition okay variable composition okay so I put up this picks so you can imagine what I'm trying to tell you what is actually element compound and okay clear till here I hope you understood the difference between element compound and mixture I hope you understand that what is exactly atom what is exactly element what is exactly compound right okay then that is all for today I hope you understood the lecture yes I hope you understood the uh depth I'm trying to tell you okay so you may put uh some questions to it you may ask comments you may ask me doubts in the comment section I will definitely answer to this okay I will see you in the next lecture again till that keep smiling be positive and take care thank you