foreign [Music] Academy and I'm nitin I hope you all have watched my previous video on physical properties if you have not please do besides I do hope you all are having a wonderful time and today in second you want science I'll be moving on to the next chapter chemical composition and let's jump straight into it okay okay for the first segment of this video I'll be going through elements so elements so uh in secondary one science uh this is something new to all of you because uh we are learning the periodic table of elements in secondary school okay so periodic table of elements okay so this is something new that all primary six students will learn in secondary school and this is the first thing that we're gonna learn elements okay so let's get started okay elements so what are elements so this is our first question what are elements so elements are the basic building blocks of all living and non-living matter okay living meaning as humans all the living things and non-living meaning just the things like uh it could be a computer would a plastic bag gold okay all of this is made out of elements okay next elements are is basically a substance that cannot be broken down into simpler substances okay so this is something important okay so substances that cannot be broken down into simpler substances and elements are also listed in the periodic table like I said the periodic table of elements okay next so the symbols for the elements are unique okay to prevent confusion and for standardization okay so for example the chemical symbol for iron IS F e and the chemical symbol for carbon is C chemical symbol for oxygen is O chemical symbol for nitrogen is n okay so there's many of this but it doesn't always have to be that uh if there's a certain element that there's chemical symbol must start in the same letter like oxygen nitrogen and carbon all of them start at the same ladder right except for iron ion the chemical symbol is Fe and sodium sodium is what and a okay so they are not always the first letter of the elements okay and also something that you have to take note is that when you're writing the chemical symbols the second letter over here is always in small letter okay it's always in lower caps never write a f e okay so this is wrong okay so just take note okay next okay now in the same topic of elements I'll be going through the periodic table of elements okay so this is the periodic table of elements and this piece of paper over here the periodic table of elements will actually be provided for you in your examinations so it will be provided for you in the last page of the examination paper okay so just ignore next so let's take a look at the points of the periodic table of elements so firstly the elements are arranged in the periodic table based on their properties Metals versus non-metals okay so basically you need to know this zigzag line over here okay so basically I'll go through this uh more in depth in the next slide Metals versus non-metals okay so for now just take note of this so metals are actually on this side okay of the zigzag line while non-metals are on this side of the zigzag line including hydrogen okay so the left side is metals okay so let me just write that down left side is metals well the right side right side is non-metals so just ignore okay so let's go to the next point now so the next Point okay elements usually occur naturally on their own as solids okay okay so let's just take a look at that elements usually occur naturally on their own as solids liquids or gases okay so all these elements over here I actually eat natural things okay so they are from nature and they appear in forms as solids liquids or gases okay so tree forms so let's take a look at the next point okay 11 elements are gases okay let's highlight the 11 elements okay so first we have hydrogen H represented by the chemical symbol of H next we have helium represented by the chemical symbol of h e next we have neon okay represented by the chemical symbol of n e next oxygen represented by the chemical symbol of O after that we have nitrogen represented by the chemical symbol of n then we have fluorine okay represented by the chemical symbol of f next CL meaning chlorine okay chlorine is okay it's a gas as well so represented by the chemical symbol F C L after that we have argon okay argon represented by the chemical symbol of a r next we have k r the chemical symbol KR what is that is Krypton okay after that we have eggs in chemicals in a chemical symbol x e is basically Xenon okay and lastly we have R and basically radon so all these yellow color highlights are basically gases okay so please do take note okay next [Music] two elements are liquids Mercury and bromide okay so the liquids let's highlight them in green color Okay bromine and bromine represented by BR and Mercury represented by HG okay okay next all the others left are solids at room temperature okay so there's no need to highlight the rest okay so I hope you understood that okay next [Music] the diversity of matter is made up of one or more elements in the periodic table okay Okay so uh something that is made up uh any any matter in this world is made up of one or more elements from the periodic table okay so any one of these elements okay next okay next we have Metals versus non-metals so I told you that I'll be going more in depth with this using the periodic table right okay do you still remember I just I just said so these are all metals okay on the left side and these are non-metals on the right side okay so here I have created a table in order for you guys to see clearly okay so metals have a shiny appearance sorry metals have a shiny appearance while non-metals have a dull appearance okay metals are malleable okay malleable while non-metals are brittle okay malleable and brittle so you have heard these two words in my previous video physical properties so Malibu means that it can be beaten into sheets so basically the metals can be beaten into sheets and it will be fine without breaking okay so that's what it means by when metals are malleable okay while brittle means easily broken okay so please do take note of these two words okay metals are also ductile okay ductile ductile meaning that they can be drawn in wires okay so I've also taught this in the previous video physical properties so I hope you understood this so please do go check out my previous video on physical properties for you to understand this chapter more okay okay metals also have high melting and boiling points while non-metals don't they have low melting and low boiling parts metals are also good conductors of heat and electricity while non-metals are poor conductors of heat and electricity okay so I hope you understood this Metals versus non-metals okay so let's move on okay for the second segment of this video I'll be moving on to compounds so let's take a look at what compounds are okay so what are compounds okay a compound is a substance that is made up of two or more different elements chemically combined together okay chemically combined meaning chemically bonded together okay okay so made up of two or more different elements chemically combined together okay so this is a what a compound means okay next let's take a look at the properties of compounds okay so let's just take note that they are made up of two or more elements okay is that it no two or more different okay different is a key word elements and chemically bonded okay together okay so this is also a q one so this means that uh this uh compound can only be separated into two elements by chemical chemical or separation techniques okay okay so separation techniques I've introduced this word to you okay separation techniques I'll be going through in the next chapter okay so uh the next chapter after this is basically separation techniques okay so I'll go more in depth about separation techniques in the next chapter okay so I hope I understood that so let's take a look at the properties of compounds now okay properties of compounds okay so for the first property of compounds is that compounds do not have the same properties as they are constituent elements so meaning that they do not have the same properties as the elements that made them meet the compounds compounds okay so they do not have the same properties as they are constituent elements okay next the second property is that when a compound is formed a chemical reaction occurs so this is really important actually all of this is really important okay so when a compound is formed actually a chemical reaction needs to occur in order for a compound to be formed okay next the third property of compounds so the elements that make up a compound are always combined in a fixed proportion by Mass okay are always combined in a fixed proportion by Mass okay so this is really important they always need to be combined in a fixed proportion by mass or else it will go wrong okay you can't make the compound that you need okay next a compound cannot be separated into its constituent elements easily okay like I said we need to use chemical means in order to separate a compound into its uh constituent elements okay so what is this chemical means okay so next okay [Music] okay so for next segment over here segment number three I'll be going through mixtures and I hope you understood about the previous segment compounds okay so let's take a look at mixtures now okay mixtures what are mixtures a mixture is made up of two or more elements and or compounds that are not chemically bonded okay so let me highlight this part it's made up of two or more elements and or compounds that are not chemically bonded okay so a mixture is made up of elements only compounds only are elements and compounds only okay meaning that they do not so it's basically a mixture of elements just only elements or only compounds or it could be a mixture of both elements and compounds okay so not chemically bonded together meaning that they can be separated using so it means that they can be separated using physical methods okay unlike the unlike unlike compounds which can be which can be separated using chemical means because it's actually harder so using physical methods okay so let's take a look at the properties of mixtures right now okay for you to understand more about measures okay a mixture has the same characteristics as is constituents okay so unlike compounds which do not have as the same characteristics as its constituents mixtures do okay next the constituents of mixtures okay do not have a fixed proportion so it can be a lot of elements and very less compounds or a lot of compounds and very less elements so there is no fixed proportion okay next when a mixture is formed no chemical reaction occurs unlike the compounds okay next that's why a mixture can be easily separated by physical methods like I said over here okay like I said okay so I hope you understood that now let's move on so in the in mixtures now actually two types of mixtures okay so let's go through these two types of mixtures in a deeper level okay the two types of mixtures okay there's two types of mixtures so let's take a look at it so first of all being Solutions and secondly suspensions okay so let's take a look at Solutions first okay a solution is basically a mixture of soluble substances okay before that there's a few vocabulary that we need to know meaning solution solute and solvent so these are the vocabulary we need to learn first okay so solution what is a solution a solution is basically a mixture okay a mixture like a mixture over here in which one substance completely dissolves in another substance okay for example salt solution is when salt completely dissolves in water okay next let's take a look at what a solute means a solute is basically the substance that dissolves in the solvent meaning like the salt the salt that dissolves in the water so in a solvent meaning so now you already know what solvent means right a substance that in which the solute dissolves it so basically it's water okay so let's just take this simple uh simple experiment so basically salt solution okay so imagine this is salt solution okay so we are like sprinkling some salt into it so this is basically the solute and this is basically the solvent and the end result will be solution okay so this will be the solution so if we understood that now let's take a look at the others okay so now let's take a look at the solution of points okay first point in terms of particles a solution is a mixture in which the constituent particles are mixed evenly okay is a mixture in which the constituent particles are mixed evenly okay so uh so it does not uh so Solutions and suspensions right so that means that the salt particles will not suspend in the water it will mix evenly and we can't see the salt particles with our naked eye okay so just like that so they are mixed evenly throughout and another thing that means that the solute particles separate and mix evenly with the solvent particles they spread evenly throughout the whole solution okay okay so they spread evenly throughout the whole solution next a solute or solute particles are too small and cannot be seen and can pass through the filter paper easily okay so if you want to try to separate the salt particles from the water particles filtration is not the best physical method because the salt particles are smaller than the physical the filter paper hose uh those is uh the filter paper holes so meaning that the particles will actually just pass through the paper and not be filtered filtered okay so that's why this is the wrong setup we won't uh get the the what we wanted to obtain basically the soft particles okay next okay so Solutions can be described as dilute or concentrated so what does dilute and concentrator mean okay so for the same volume of solvent okay so let's imagine so that's a volume of solvent over here so let's just imagine okay our daily is on a solution contains less solute meaning less less salt okay while a concentrated solution contains more solute meaning it contains muscle so this solution over here is more concentrated while this solution over here is dilute okay so I hope you understood that okay okay so now let's move on okay now let's go through suspensions okay so suspension is basically a mixture of insoluble substances okay a suspension is a mixture that contains insoluble substances in a liquid or gas so insoluble substances meaning like sand and water okay next the solid particles in the suspension do not dissolve unlike the salt okay when a suspension is left to stand the solid particles will settle to the bottom of the mixture okay so uh for this case let's say sand okay so when a suspension is left to stand the sand particles will settle down to the bottom of of the mixture because the sand particles are actually uh I actually insoluble substances so that's why they do not dissolve and in water okay so that is why they were settle down to the bottom of the mixture and they will not mix evenly with the solution with the solvent okay solvent meaning water okay okay when a suspension is filtered the solid particles will form residue so residue is basically the sand that is left on the filter paper and uh and the mixture that is being filtered and though what you're obtained after you filter the filter the suspension is basically the water right the pure water so that water is basically the filtrate okay so let's take a look at our filtration setup that I've drawn over here so this is a filtration setup okay so this part over here is the residue okay and this over here is the filtrate and I hope you can recognize these two uh lab apparatus so this being the filter funnel so this line over here total Fallen so let me just write that down filter funnel so this this is the filter paper and this is the beaker okay so residue so residue is basically the insoluble substance in a suspension too big to pass through the filter paper so they are retained okay and filtrate is basically the liquid part of the suspension and they may contain solute dissolved in solvent okay so if we have this setup over here basically that's a beaker anyway sorry let me draw it properly so imagine if that's a beaker over here and this solution that is salt and sand okay so this over here is basically the sand and the soft particles are just around okay so after we filter it what are we supposed to do we are going to do something using the evaporation okay so this is slightly into the separation technique so in the first video of a scientific Endeavor I've shared slightly on this so basically where we have an evaporating dish okay wait sorry let me draw that properly basically where we have a evaporating dish a wire gauze okay and a tripod stand okay and over here we have a we have a Bunsen burner okay so Heat so this is the setup and you put the solution and after all the water has evaporated we get salt at the bottom okay so this is the setup that I've taught you in my first video so it's just I only explain slightly on it so in the next video I'll explain more of this uh this physical methods more deeply okay so with that let's move on okay next let's take a look at Solutions versus suspensions in the form of a table for you to see more clearly okay okay Solutions versus suspensions okay this is supposed uh this is in a table format because examiners ask this very very common exam question what uh like give two differences between Solutions and suspensions or give three differences between Solutions or suspensions or state all the differences between Solutions and suspensions so there's many many varieties that they can ask this question in okay so let's take a look at the differences between uh the solutions and suspensions okay so firstly Solutions are homogeneous meaning the color density physical and chemical properties are same throughout the solution okay so they are same through other solution while suspensions over here are heterogeneous okay meaning that they are color density physical and chemical properties are totally different throughout the whole solution okay Solutions when it's left to stand on its own the solute does not separate from the solvent okay while in suspensions when it's left to stand on its own the insoluble solids settle to the bottom of the container okay okay when Solutions are filtered no filter particles will remain on the filter paper because the particle size is actually too small uh and it passes through the filter paper really easily while for suspensions the insoluble solids are obtained on the filter paper because they actually are too big to fit through the filter paper okay their particle size is too big larger than the the filter papers pause and thus it does not pass through and only the solvent is obtained okay so in Solutions light can pass through fully while in suspensions like cannot pass through fully okay so this is just a brief summary of what we have already learned in Solutions and suspensions from the past two slides okay so I hope you understood this now let's move on okay next solubility segment number six okay let's take a look at solubility [Music] case what is solubility solubility refers to how well a solute dissolves in a fixed volume of a particular solvent okay how well a solute dissolves in a fixed volume of a particular salt okay so the key word is how well okay so first uh now that we know the definition to solubility let's take a look at the factors affecting solubility so this is something that they will test you in exams the factors affecting solubility okay so let's take a look at the first Factor the first factor is basically the nature of the solute solute mean what you're going to dissolve into the solvent okay so different solutes have different solubilities in the same solvent even for two different solutes that can dissolve their solubility in different solvents is different okay so different solutes have different solubilities in the same solvent okay even for two different solutes that can dissolve their solubility in different solvents is different okay so I hope you got that nature of the solvent next the solubility of a substance depends on what the solvent is okay the same solute has different solubilities when it's placed in different solvent okay meaning that if we have a solute called salt right and we place salt in water it has a different solubility than when we place Salt and alcohol okay next for solutes which are soluble in two different solvents the solubilities are also different meaning that for solute that is soluble in two different solvents right each of the solubilities are actually different okay okay next Factor we need to take note is the temperature solubility increases with increase in temperature the hotter the mixture the greater the amount of solute that can dissolve okay so the hotter the mixture the greater the amount the solution dissolve okay so uh in examinations right they will ask you uh with like some experimental setup they will ask you this question so how can we increase the solubility of the substance in order for it to dissolve faster in the and I'll solve it okay so basically what we can tell right is to tell them that okay we can increase the temperature of the uh of the solute so that the so sorry we can increase the temperature of the solvent okay obviously the whole mixture so that the greater so that there's a greater amount of solute that can dissolve in the mixture faster as well okay so this is something that you have to take note okay so next okay so just like solubility let's go through the rate of dissolving okay the rate of dissolving the rate of dissolving refers to how fast a solute dissolves in a solvent okay so dissolving refers to how fast a solute dissolves in a solvent we can measure the rate of dissolving of a substance by measuring the amount of substance devolved dissolved per unit time okay next so let's just take a look at the factors of factors affecting the rate of dissolving one being temperature okay the higher the temperature of the solvent the faster we can expect the solute to dissolve okay so this is something that is commonly tested okay rate of dissolving so they have different different scenarios when they are testing this rate of dissolving okay so they will tell you like something like okay so there's this sugar particle and this other sugar particle so um and these this Beaker over here has a temperature of 25 degrees and the other Beaker has a temperature of 30 degrees so which which uh which bigger when we put the sugar in will dissolve faster so you have to like say it's the the one which is 30 degrees Celsius because the higher the temperature of the solvent the faster we can expect the solute to dissolve so that's how you're supposed to like explain it okay so the next Factor size of the solid particle so this is something that has big effect in the in the rate of resolving so let's take the same example okay now so let me draw it out okay 25 degrees Celsius and this one 30 degrees Celsius so here we have big salt sugar particles okay and here we have small sugar particles okay so the big ones will take a longer time to dissolve okay oh let's take out the the temperature let's just say that both of them are 30 degrees then only it will be fair Okay so um the bigger particles right the biggest sugar particles will actually take a longer time to dissolve because they have a larger exposed surface area so oh sorry they have a smaller exposed surface area so it takes a longer time for it to dissolve well whereas the smaller sugar particles have a largest surface area so that it dissolves faster okay so smaller okay so smaller the sugar particles the sorry the solid particles the faster we can expect the solute to dissolve small particles actually have a larger surface area that comes into contact with the solvent okay okay so this is basically what I've explained okay okay next rate of stirring the faster the rate at which we stir the mixture the faster we can expect the solid to dissolve okay so these are the three factors affecting the rate of dissolving okay so I hope we understood that now let's move on [Music] okay so for Segment number eight of this video how can we distinguish between elements compounds and mixtures okay okay so how can we distinguish between elements compounds and mixtures so there's a table here elements compounds mixtures so the composition of elements compounds and mixtures so elements are made up of only one element okay compounds two or more elements mixtures two or more different elements and are compounds the properties of elements none compounds different from the constituents of a mixture similar to constituents the proportion of constituents for elements none because there's only one element and compounds is fixed and mixtures are not fixed for the proportion of constituents elements the formation they are form mostly naturally and for compounds they are formed using a biochemical reaction and for mixtures they are formed using physical change okay next for element separation of constitutions you can't separate because there's only one element over here okay so there's only one element so you can't separate while for compounds we use chemical means in order to separate so chemical means such as electrolysis and for mixtures physical means so the separation techniques that I'll go through in the next video okay chapter four so physical means so with that this is how you distinguish between elements compounds and mixtures okay so this is it so with that I've come to the end of this video okay thanks for watching everyone I hope you have enjoyed this video and understood more about secondary one science the third topic of chemical composition and I hope this really helps you if you're not subscribed to Newton Academy please do subscribe and be a part of our family I'll see you again in my next video bye foreign