00:02 Good day, everyone.

00:14 My name is Charles Christopher.

00:16 I'm the chemistry teacher,

00:18 and I'll be taking you on the topic solution and solubility.

00:23 Now, before I begin, I would like to give you

00:27 the objective of the lesson.

00:31 Now, at the end of the class,

00:33 the students should be able to explain what solution

00:37 solute and solve it means, respectively.

00:40 The students should be able to define solubility

00:45 of a solute in a solvent.

00:47 Now, the students should be able to also define

00:50 the following terms, saturated solution,

00:53 unsaturated solution, and super saturated solution.

00:58 And also be able to leave the factor

01:01 that affects the solubility of the solute

01:03 in a given solvent.

01:06 Now, lastly, be able to perform calculation

01:10 evolving solubility and draw and explain

01:13 the solubility call.

01:14 Now, what is solution?

01:18 What we'll take about the solution

01:21 of a particular substance,

01:24 we're talking about a uniform or a homogeneous mixture

01:28 of two or more substances.

01:31 Now, basically, solution is made up of two

01:35 principal factors, which are solvent and solute.

01:39 Now, I want to talk about solution.

01:40 Basically, as you are saying in this equation,

01:43 it's showing you that, okay, solution

01:44 is actually equal to solvent plus solute.

01:48 When you dissolve a solute in a solute,

01:52 you have what we call a solution.

01:54 Just like I can see in this picture here,

01:56 the various aspects of a solution, all right?

01:59 So you see that is a solute, this side is a conical flux,

02:02 that you have a lump, okay, which is a solute.

02:05 Now, giving you that solution, you are saved there, all right?

02:09 So now, a solute, what is a solute?

02:11 Now, a solute is a dissolved substance,

02:14 which may be a solid, a liquid or a gas.

02:18 Why a solute is principally a liquid?

02:22 Which dissolve a solute, all right?

02:26 Take note of that.

02:27 Now, let us have some examples.

02:28 We'll talk about our solution.

02:30 We have this example.

02:32 Now, an example of a solute solution is brats, okay?

02:37 So now, this one is a solid in a solid, that's brats.

02:41 The another example of a liquid solution

02:43 is Akios hydrochloric acid, which is x here in water.

02:50 Another example of a gaseous solution is air, all right?

02:56 So, take note of it.

02:57 So, typically we have solution type, then we have example.

03:02 Then here, you're having a gas in a gas,

03:04 dissolving the gas in a gas, an example of that is air.

03:08 Then you have a gas dissolving the liquid,

03:10 an example of that is a carbon dioxide in soda.

03:14 Then a gas in solid, a very good example of that

03:17 is a hydrochloric gas in palladium metal, all right?

03:21 Then another type or category of solution is a liquid in a liquid.

03:27 So, an example is a gasoline.

03:29 Now, of course, your PMS, your PMS,

03:31 which is, another example, PMS, your normal motor or vehicle or fuel,

03:40 that we use in following our vehicle, that's your gasoline,

03:43 which is also known as PMS, all right?

03:45 So, now, another example of this also is a emulsion.

03:50 That's what's called like your pants.

03:52 It's also an example of this liquid in liquid,

03:54 all right, type of solution.

03:56 Now, a solid liquid solution,

03:59 an example of that is a sugar in water, all right?

04:02 Now, later, we're going to find out that,

04:04 you see, the more increase in temperature you have

04:09 in a particular, let's say, a 6/10, all right?

04:12 So, like, for example, sugar now, the more the sugar would dissolve.

04:16 But if the temperature is low, the effect of the solution

04:19 of sugar would be very low, all right?

04:21 Because the temperature is low.

04:22 So, the higher the temperature, the more the sugar would dissolve.

04:25 So, you'll find out later as we go out.

04:26 So, another type of solution is called liquid in solid.

04:31 A very good example of that is mercury delta amagam, all right?

04:35 So, the last one is solid in solid.

04:38 Now, sterile silver, it's just like a coin, all right?

04:41 That is using most of the most of the countries, okay?

04:45 So, now, solid in solid, an example of that is a sterile silver, all right?

04:50 Then, now, how do we characterize a solution?

04:55 Now, characteristics of solution.

04:57 Now, it can cause solution to exhibit several properties.

05:00 Now, but one is that a solution consists of homogeneous mixture.

05:04 We know that from the definition, all right?

05:06 So, another thing also is solution is composed of one phase.

05:10 One phase in the sense that it is solid to be solid or true.

05:13 Now, if it is liquid to be liquid or true, then if it is a gas to be gas or true,

05:18 just one phase, no more than one phase, that's a solution.

05:22 Then, also, now, particles in the solution are not visible to the naked eye.

05:28 Of course, you can see it through, just like you pour your milk, all right, in water.

05:33 So, you pour your making water.

05:34 So, the solution you have in that mixture water, you will be able to see through it.

05:40 Now, later, you will find out that a solution in which you cannot see through, all right?

05:45 You'll find out that that kind of solution to call a colleta solution.

05:49 And, a colleta solution can be scattered by lights.

05:52 Now, the scattering of light, take notes.

05:54 Maybe in case, as it let you go, or you'll find out that it's scattering of lights,

05:58 all right, over a colleta solution to call it to that, in fact.

06:02 You'll find out that later as we go in the lesson.

06:05 Now, components of a solution cannot be separated using simple mechanical features,

06:10 like your normal temperature techniques.

06:12 You can't actually separate it through that means, okay?

06:15 Now, let's not know the difference between a true solution and a colleta solution, all right?

06:23 A true solution is for when solute particles dissolve in such that they are able to get

06:30 in between the solid particles, take note of that.

06:34 In between the solid particles, that means you can see through it.

06:36 That's a true solution, all right?

06:38 An example of true solution is a cure solution of sodium chloride, your common sort.

06:43 And, copper true tetraoses of the C, why you mix them together?

06:47 Of course, you'll be able to see through the crystals of these copper salts, okay?

06:53 So, then, again, a first solution or a colleta solution, don't take note of that.

06:58 That a first solution, so known as a colleta solution, is one in which the individual particles

07:05 are larger than the particles of the true solution, but not large enough to be seen by the naked

07:14 eye.

07:15 So, examples of collets are starch and abumé.

07:19 Now, we know what an abumé is, an abumé is just a white spot, that is a white part of

07:25 egg.

07:26 You know, there's a yolk, there's the abumé, all right?

07:28 So, it's an example of a colleta solution, like a colleta solution.

07:32 Now, we have types of collets, so now, basically, when we talk of collets, so we talk of a solution

07:40 that is forced.

07:41 Now, we have various types of these collets, in various form, in which you can actually identify

07:46 this.

07:47 Now, we have shows and gels, shows and gels is a type of colleta solution.

07:53 These are collets, where solid particles are dispersed, in liquid medium.

07:59 A very good example of that, some examples of that are starch, glue, jelly, like your petrullo

08:06 jelly is an example, so take note of that.

08:08 Now, we have aerosols, now, in aerosols, liquid particles are dispersed in a gas.

08:15 So, dispatching a liquid in a gas, so to call, aerosols, take note of that, a very good example

08:22 of that is your fog, okay?

08:25 Fog, we have a smoke, we have a spray of a synthesizer, our example of aerosols, okay?

08:31 Now, a motion, now, for emotions, a liquid is dispatched in another liquid, all right?

08:37 That liquid in liquid.

08:40 And examples of emotions are milk, who have milk is an example, your hair cream, that

08:46 is a cleaning action of detergents, is actually due to the ability to form a motion solution,

08:53 take note of that, okay?

08:55 So, now, properly, we are going to, because of the lexin, we just repeated the previous one.

09:01 So, let's now look at what is solubility, because we'll be talking about solution, our

09:06 solution may probably, you have one substance dissolving in another to form a solution.

09:11 So, now, let's now look at what is solubility?

09:15 What is the effect of solubility in various substances that are dissolving in other substances?

09:23 So, let's look at the, this, what is solubility?

09:25 Now, we're talking about solubility, solubility of a solute or a substance in a solvent at a particular

09:33 temperature is a mass more amount of solute in more grams that we dissolve in one DM cube

09:39 of a solvent, all right?

09:41 Now, what DM cube is solute about at a particular temperature, they must be at that temperature?

09:47 So, the moment that temperature increases, of course, the dissolution, the dissolution

09:51 effect will change, will not be the same, okay?

09:53 So, that is all called solubility, is actually the amount, the mass amount of solute, all

10:00 right?

10:01 It moves on grams that will dissolve in one DM cube of a solvent.

10:06 So, now, the fact is, a solute and a solvent be present to form a solution, that is the

10:10 effect of solubility in, okay?

10:12 Now, the concentration in more per DM cube of a saturated solution is the solubility of

10:19 the substance.

10:20 Now, solubility of substance, when you express it in more per DM cube, of course, you have

10:25 it in a gram, that the concentration in gram times molar mass, that's the formula we

10:31 use in case, possibly as we go on because there are calculations also we're going to carry

10:34 out here to know how to calculate, how to find out the solubility of a particular substance,

10:42 all right?

10:43 So, we can use a chemical equation or chemical formula to actually find out of this, can

10:50 use some formula to actually calculate this.

10:52 Okay, now, the molar mass, that's the molar mass, now basically in terms of more per DM cube,

10:59 so solubility is coming to express also as mass times 1,000 all over molar mass times volume.

11:08 Now, how this is actually gotten is, we know that solubility from the definition, solubility

11:14 is equal to not the most of solute all over volume of solution.

11:21 Volume of solution is in one DM cube, don't forget that, express in 1,000, okay?

11:26 Then now, by the time you are ready or mathematics, you'll find out that we arrive at this particular

11:37 formula, take notes of it, okay?

11:39 So, that is what we use to calculate the solubility of a solution, okay, of the particular

11:46 substance.

11:47 So, then now solubility in gram per DM cube is also expressed as mass times 1,000 all over

11:53 volume times 1, okay?

11:54 So, by the time we are carrying out calculation, you'll find out how all these formulas can

11:58 be put into use, take notes of this, okay?

12:03 So, now, solubility of a solid solute, in a solid, increase it with rise a temperature,

12:10 I've said this before, that when the temperature increases, so the solubility will also increase

12:17 for solid and liquids only, but for gasex, the solubility will decrease with rise a temperature,

12:27 so many that when the temperature increases for gasex, so the solubility will work with

12:31 decrease, take notes of that.

12:33 So, now, before we go into other things, so let's look at some definition of terms for

12:39 you to be able to understand the calculation of the solubility and also solubility curve,

12:43 okay?

12:44 Now, first, what is a saturated solution?

12:48 Now, in this case, a particular solution is a kind of solution whereby the sub sign is

12:56 able to exhaust more that it can actually, ordinarily, absorb in the presence of all dissolved

13:03 solutes, don't forget that.

13:05 Now, a saturated solution at a particular temperature is one which contains as much

13:10 solutes as it can dissolve, at that particular temperature in the presence of all dissolved,

13:15 meaning that there are some, all dissolved that are still present, that are still there.

13:20 Such a solution becomes saturated, that means it's full, it's saturated, it can take more

13:26 that it can actually, it can actually absorb or dissolve in the presence of all dissolved

13:32 or solute, take notes of that.

13:34 So, now, another category also of the term I want us to look at is all saturated solution,

13:40 of course, this one is not full at all, this is a type of solution whereby the substance

13:47 or the solution contains less of the solute that it can actually dissolve at that particular

13:52 temperature, okay?

13:53 So, take notes of that.

13:54 Then, lastly, we have a super saturated solution, so this one is like saying over full of

14:00 it, all right?

14:01 Now, this is a solution, we contain more of the solute that it can dissolve at that temperature.

14:07 So, this one, it will continue absorbing more, continue taking in more of these solutes.

14:14 Now, even when the temperature, if I, when you increase the temperature, so that's when

14:18 it will even absorb more, so that's a solid water, and that's a stage of the solution,

14:23 don't call super saturated solution, so take notes of that.

14:26 Now, let's look at the solubility curves, all right?

14:29 Now, what we're talking about solubility curves, now, this is actually a curve that shows

14:35 you the various sorts, the solubility or the various sorts, against the temperature,

14:43 your other temperature is increasing or decreasing, all right?

14:46 So, we're going to look at that, the effect of temperature, all right, of some sorts, all

14:52 right?

14:53 So, what will happen to the solubility, is it going to increase or decrease?

14:56 That is a solid water, this solubility curves helps out to understand.

15:00 You will know whether when you have increases solubility, so what happens to the temperature?

15:06 With the temperature, increase or decrease for solid and liquids, then for gases, of

15:11 course, like I mentioned before, when the solubility decreases, so what happens to the temperature

15:16 of the gas, so it's with what, increase, don't forget, it will increase, right?

15:21 So, now, that's actually what we are saying, these are actually grass or solubility

15:26 gas temperature, so the graph actually provides useful source of what, of information, as you

15:34 can see here, let me just explain this to you.

15:36 So, actually, you see this K.I, this is potassium iodine, so for potassium iodine, it's quite

15:44 understandable, so this is very clear.

15:46 So, for potassium iodine, at zero degrees Celsius, as you can see now, you see that the solubility

15:52 is one rattety, as you can see there, it's one rattety more per DMQ, all right, as you can

15:57 see there, depending on the unity, sometimes you can have more per 100 gram H2O, that is the

16:03 water, here, this is standard solubility, I use it here, all right, so you see that here

16:08 in the chart, you see that 130 or around 129, all right, so this, the temperature is actually

16:15 at zero, so now, you see the 4K, I look at, it's actually what, it's an AQ, solution, it's

16:21 AQ.

16:22 And when the temperature increases, as you can see, between here, when the temperature increases,

16:28 so the solubility also increases, as you can see, right, now, because, don't forget, we

16:33 said something about solid solute and liquid solute, when the solubility increases, what happened

16:40 to the temperature, the temperature increases, that's exactly the effect here, just watch the

16:44 chart, you see, then for this one, so the own nitrate, you see that it increases, it started

16:49 with 70 or 72, as the case may be, as the temperature was increasing, so the solubility was also increasing

16:56 as well.

16:57 Then look at the potassium nitrate also, as the temperature increases, then the solubility

17:02 increases, as you can see, the curve, like this, all right, then now, all that's also,

17:06 you have ammonia chloride, the same thing, increases like this, then you have potassium

17:11 chloride, as you can see, but another thing I wanted to take notes here, is that if you

17:16 watch this ammonia, all right, you see that ammonia decreases, as the temperature was increasing,

17:23 so you see the curve comes down, like this, why the curve, there's increasing temperature,

17:27 all right, then also, if we check out that also, which are not also here, because this one

17:32 is not a complete chart that is playing all the various salts, that is solid solute,

17:39 liquid solute, or gaseous, as the case may all the different substances that we have,

17:43 so because this graph cannot just as bring all of them together, so you can actually pick

17:49 three of them and plot a chart on your own to actually help you to understand the solubility

17:55 of that, but those substances you probably have, or maybe you choose, then it gives temperature,

18:01 okay, at temperature increases, don't forget, so the solubility of solid and liquid will

18:06 also increase, so then for gaseous, at temperature increases, so the solubility will work with decrease,

18:12 so take note of that, so this is a chart showing the various of substances based on the temperature

18:17 change, okay, now solubility increasing with temperature, I've said that before most, for

18:23 most substances, for example, moisture will dissolve in hot water, I've measured this

18:28 earlier than in cold water, why because there's increasing temperature, so increasing temperature

18:33 will make moisture go to dissolve, all right, then the solubility of gaseous displays opposite

18:38 relationship, like we said, increasing temperature will lead to the decreasing solubility of that

18:45 gase, now the chart also means versus the temperature, notice our solubility tends to increase the

18:51 increasing temperature, of course we've said this before, for salt and also for gaseous, all right,

18:55 now let's now look at factors affecting solubility, now number one factor is temperature, we've said

19:02 this before, even from the chart that explained that before, all right, of a given solute in the

19:06 given solvent, typically the pace of temperature, for many solids, so dissolve in liquid water, solubility

19:14 tends to correspond with increasing temperature, who've said all this before, so now for us, for water

19:20 molecules it also, the vibrates more quickly and are better to be able to interact with and break

19:27 apart the solute, of course, that is what, because the temperature has actually caused that

19:32 in increasing temperature, it's called the increase in the movement of the molecules that we have

19:38 in the solution, okay, now another factor is pressure, now for pressure, like we said, pressure

19:45 really don't have effect on solid solute and liquid solute, except for gases, all right, now because

19:52 the pressure has negligible effect on the solubility of liquid and solid solutes, but it has a strong

19:59 effect on solution with gaseous solute, okay, now this is apparent every time you open the soda

20:07 can, all right, the hisi sound from the can is due to the fact that it's content are other, sorry

20:16 under pressure, which ensures that the soda state is carbonated, now we'll talk about carbonated,

20:22 we mean that the carbon, carbon dioxide state is all in solution, okay, that is what we made by

20:28 carbonated drink, for example, mini, that you have carbon for that is all in that particular drink,

20:33 that's mini or carbonated, so the take away from this is that the solubility of gaseous tanks

20:38 will correlate with increasing pressure for gaseous techniques of that, so for polarity,

20:43 now there's a popular saying that actually goes here that say like dissolves like, okay,

20:50 like dissolves like, so now basically for these statesmen, so indicate that the solute

20:54 with dissolved becks in the solvent that has a similar chemical structure, just like for example,

21:00 if benzene can only dissolve in naphthalene, you don't expect water to dissolve in naphthalene,

21:07 not expect water to dissolve in benzene, because the chemical structure are different,

21:13 the functional group in each of them is totally different, so that is polarity, he assumes you

21:18 that, okay, now the ability of the solvent to dissolve various compounds depends primarily on

21:24 eggs of polarity, okay, for example, a polar solute such as sugar is very soluble in polar water,

21:31 why because the chemical structure are the same, so let's soluble in moderately

21:37 our polar methanol why because the chemical structure is a bit different, so I'm

21:43 practically insoluble in our polar solvent such as benzene, of course, water can never dissolve in

21:49 benzene because they are chemical structure, they are chemical make up are totally different,

21:55 all right, so that is why water cannot dissolve in benzene, so we call it dissolve this benzene in

22:00 naphthalene or ethyl, all right, so now in contrast in our polar solute such as our naphthalene is

22:07 insoluble in water, of course, we measure that already, but moderately soluble in methanol

22:14 and highly soluble in benzene, why because the chemical make up of benzene and I mean naphthalene and

22:22 benzene are the same, so that is why they can easily dissolve in it, now solubility chart, of course,

22:28 the solubility chart shows the solubility of many sorts, sorts of alkaline metals, for example,

22:34 an ammonium or salt, as well as those of nitrate and acetate are always soluble, we know that

22:40 techno of this water is very important, all right, now carbonates, hydroxides, sulfates,

22:48 full speeds and their heavy metal salts are often insoluble, techno of them are often insoluble, so of

22:56 course you can see from what we are seeing here, now all these later represent something, I need to

23:02 explain this to you, now X represents soluble, there this one at all, there is no effect between,

23:08 between that, that's what this one means, all right, then this one, of course soluble you are

23:13 seeing here, then the one you see small X and big X, mean that is spirally soluble,

23:19 spirally soluble, that's the meaning of this one, all right, then now when you see this I,

23:25 I means it's insoluble, that's the meaning, now meaning that this sort that is for between

23:32 aluminum and bromide, all right, maybe possibly you have aluminum bromide, okay, so it's a soluble

23:39 sort, okay, it's soluble, that's a soluble thing, water is soluble, okay, so as shown also for ammonia,

23:44 you have it, ammonia and bromide, the same calcium and bromide, the calcium and this carbonate here,

23:51 that is you have calcium carbonate, for example, calcium carbonate and water is insoluble,

23:56 techno of that, that is I here, you are seeing here, okay, so now the chart actually helps you to

24:00 explain the effect of solubility of various sorts with the various chloride, bromide, you know,

24:08 and all that, you know, with the various metals and all that, so now it tells you which one is

24:15 more soluble, which one is insoluble, which one is spirally, you know, soluble and all that, that's

24:20 what this one is, but solubility is not sort and gas solute in a liquid solvent, okay, so that's

24:26 a solubility chart, of course, we've said that before already, that solubility is a sort form from

24:31 cations on the left, of course, as you can see it on the left, all right, then an anions on the top,

24:38 as you can see it here, all right, are designated as the insoluble, but I've explained insoluble,

24:45 then slightly or spirally, that's the meaning of this, this, and I use slightly or spirally,

24:50 is the same thing, all right, or soluble, take note of that, so use these solubility curves,

24:56 now what is the essence of this solubility curve, haven't got it some fact or information from

25:02 these solubits, or what does it help us to do, so now about one is that it provides you three

25:05 formation about suitable solvent and temperature we can use for solvent extraction, okay, so that's

25:13 on that's a special process, so now when you want to carry out a solvent extraction, okay,

25:19 so like what we use in extracting oil from castor, oil from Moriga, from NIM, you know,

25:26 this is a various seed we have, so we use solubility extraction to actually carry out some

25:31 special processes in them, so now this solubility curve helps you to know the right

25:37 solubility and temperature, this minimum optimal temperature you can use to actually carry out

25:42 this solubility extraction process from natural sources, all right, so then number two,

25:47 it provides you three for mixture about temperature for fractional crystallization, mixture or soluble

25:53 sorts, all right, so that's that, then because also enable pharmacist to determine the amount of

26:00 solid drugs that must be dissolved in a given quantity of solvent to give a prescribed drug

26:07 mixture, so that is what that helps us to do, so quickly, so calculation of solubility,

26:13 now already we'll give you some questions, we'll give you some, I mean sorry, we'll give you some

26:19 formulas, some basic terms about our solution and solubility, so let's not see how we can actually

26:26 implore all this into our calculation, so when we are giving a question, for example,

26:31 we have this question that says, if 12.2 grams of lead nitrate, we are dissolved in 21 CMQ

26:40 of distilled water at 20 degrees Celsius, now we're actually calculating the solubility of the solute

26:47 in more PDNQ, don't forget, we said that solubility can be expressed in more PDNQ, it can also be

26:53 expressed in ground PDNQ, don't forget that, all right, ground PDNQ, but here they are

26:58 actual to express in more PDNQ, now already here you have to bring out what is it that we're giving,

27:04 here, we are giving basically the mass, all right, then now we're giving the volume,

27:12 take note of that, all right, we're giving the mass and the volume, but you see, I need to know

27:19 here the amount of moles, or the number of moles of this lead nitrate that dissolve this 20 or 21

27:27 CMQ of distilled water, so what do I need to do, I will need to calculate this one first of all,

27:32 cover this one to more, so what do you carry out this, now to do that,

27:37 now to do this, we look at this solution, first of all we need to know the mass of water, the

27:44 molar mass of lead nitrates, now lead is 207, lead is 207, then our nitrogen is 14, oxygen is 16,

27:57 but the time you carry out all the addition, you know, the mathematics, so you arrive at 331 grams,

28:03 then number of moles of lead nitrates, now from a knowledge of more concept, you are grouped with

28:10 me that, that number of moles of any substance is equal to mass of gram all over molar mass,

28:16 and here it gives us the mass to be 12.2 grams, so that is what here, we put it here, that's the mass,

28:23 a gram, that's it there, then all over molar mass, the molar mass we calculated, which is 6,

28:28 so at the end of the day, so when we divide this one by the mathematical, this is what we have,

28:32 okay, so now we keep this aside, now for this now, we can now look at this quantity, this amount,

28:41 how many of it dissolve this 21 CMQ of distilled water, so if 21 CMQ of distilled water,

28:47 all right, at 20 degrees, so don't forget the temperature given, 20 degrees Celsius, dissolve this

28:52 more we calculated, 0.037 more salt, now if this one dissolve this, so if we are to make this 21 CMQ

29:01 to 1000 CMQ, what would be the solubility, that was the question, all right, so finally,

29:07 by the time you multiply this one, you multiply 0.037 by 1000 divided by 21, at the end of the day,

29:17 your answer is going to give you this, that's 12, 176, 176 more of lead nitrate per DMQ of

29:29 a solution, okay, of that of water there, of water as the standard solvent that was used there,

29:37 so another example is this, here they say 1.0 DMQ of an Acure solution, so if you go on and on and on,

29:44 you find out that all of them they just, they are trying to explain the same concept,

29:48 the same thing they are saying, like here now they give you volume, they give you more two

29:53 salts are evolved here, one is 104 grams of potassium nitrate and 245 grams of potassium

30:03 chlorides, all right, so these are basically two salts and both of them they are made up to 1000 CMQ,

30:11 at a particular temperature, at a temperature they give to us there was 90 degrees Celsius, okay,

30:16 so the question they are asking out here is to determine which of the two salts we separate out

30:23 where the solution is good to 60 degrees Celsius, now look at it, from 90 to 60 degrees Celsius,

30:30 which one we crystallize out, is it going to be lead or potassium nitrate or it's going to be

30:34 potassium chloride, so from our calculation we will be able to find out which one is which one,

30:39 now another question also the answer alongside with that is mass or salt that would separate out

30:45 as 60, at that 60 degrees Celsius, okay, so now take notes that first before you can carry out

30:50 this calculation you need to know the solubility of lead, I mean sorry, potassium nitrates in water,

30:57 at that 60 degrees Celsius, so in bracket we're giving here to be 5.1 for more per DNQ,

31:05 for potassium nitrate, then for solubility, for that of solubility of potassium chloride in water,

31:13 at that same temperature of 60 degrees Celsius, so it's 1.6, 1 more per DNQ, so now

31:19 presented these all these facts all together in calculation, we found out that first of all let

31:25 deal with the one of potassium nitrate, the number of moles of potassium nitrate, so don't forget,

31:30 we're always referring to this, that to calculate the number of moles of any substance,

31:35 so the formula is mass, the gram all over molar mass, don't forget that, all right, so if you divide

31:40 this one they give to us 104, all right, of potassium nitrate divided by the molar mass is 101,

31:48 all right, then on the day you have 4.0 moles, okay, now that 4.0 mole, when you make it up to 1 DNQ,

31:57 actually we make it up to 1 DNQ, we're going to have 4.0 mole per DNQ, that's true, that's how they go,

32:04 you know it's 1, so multiply 1 by this, that's not effect, you'll see how the same thing

32:09 as that, so now, number of moles of potassium chlorides, if you divide this one by the, you have 2,

32:15 so also it's made up to 1, this is more, actually, but when you make it up to 1 DNQ,

32:22 but 1,000 CMQ of the solution, so you're going to have the same as 2.0 mole per DNQ, so now,

32:28 from this calculation analysis, you'll find out that the solubility of potassium chlorides

32:35 as it is a good cell choice, of course, we're giving to be 5.1 for mole per DNQ,

32:40 is higher than the amount in solution, the one we calculated in solution, which is 4.0

32:47 mole per DNQ, then what that means is that, potassium nitrates, all right, we remain, sorry,

32:54 we remain in solution, why potassium chlorides, we actually crystal out at 60 degrees Celsius,

33:01 things, exolubility at that 60 degrees Celsius is lower than the amount in solution,

33:08 so you find out that what we do here is to know the mass of salt that will separate out at 60

33:13 degrees, first of all, the difference between the moles we calculated at the one giving from the

33:17 chart is 2.0 minus 1.6, so at the end of the day, this is what you have, so you're going to have

33:23 this at the end of the day in mole, but we need to convert this mole to water to mass,

33:29 all right, because the actual is a mass that will crystal out, okay, that will crystalize out,

33:35 so now, to do that, we need to multiply this number of moles by the molar mass of water,

33:41 of that potassium nitrates, which is 1, I mean, potassium chlorides, which is 1, 22.5,

33:51 you multiply by 0.39, so at the end of the day, you have 47.78 grams of the salt, okay,

33:58 so that's that, that's how the calculation is actually done, another example, of course,

34:03 is that this one is almost the same thing, all right, but this one is a bit different here,

34:06 we are giving two salt again, all right, okay, but the same sort rather, so by different quantity,

34:15 okay, here this one is 1,800 grams per this, now, don't forget what we talked about,

34:21 saturated solution, this solution in low is saturated, meaning that for me to know the total mass

34:27 here, that is actually inside this solution, so in the presence of all dissolved solution,

34:36 so we need to add this one to this, at this particular temperature, then add this one

34:41 to this, all right, so at this particular temperature, so now, at the end of the day, of course,

34:46 now what the actual here is to calculate the mass of potassium nitrate that will crystallize out of

34:52 solution, if you see the mass has changed now, all right, if 155 grams of the saturated solution

35:00 at 83 degrees Celsius, it's cool to 14 now, all right, so that is why you see my calculation,

35:05 I carried out here was that the saturated solution of potassium nitrate at 83 degrees Celsius,

35:10 so we need to add it, so here you see this, this, but this, make up to this, so at the end of the day,

35:17 of course, we added this to this, we have 2800 grams, all right, of the saturated of

35:24 solution of potassium nitrate, then saturated solution of potassium nitrate again, when the temperature

35:29 drops to 14, so we add this, that's 700, that make up that, I mean the 1000 make up the 700, so of course,

35:36 you add it to 1000 to 700, you have 1700, now at the end of the day, what we do here is to find the

35:44 mass of solution that was deposited, don't forget, because we said the saturated solution is actually

35:49 a type of solution that can actually dissolve as much solution, all right, as it can dissolve,

35:54 in the presence of all dissolved solution, so in the presence of all dissolved solution, we'll find

35:57 the difference between these 2800 and 1700, at the end of the day, you have 1100, now from where,

36:06 from 83 degrees Celsius to 40 degrees Celsius, so now 2800 or saturated solution deposited this,

36:13 don't forget, this is undissolved solute, right, now if this one dissolve, contains this one,

36:20 that deposited this, now whether not change the mass now to 155 grams, so of the same saturated

36:27 solution that it became saturated still, all right, so what would be the deposit of platinum,

36:35 this one of the saturated solution, when the temperature drops from this to this, so at the end of the day,

36:40 when we carry out the calculation, this is what we have, all right, so that is just how the calculation

36:47 is done, all the calculations are actually done here, so now the evolution here, I want to give you

36:53 here is that you are going to actually define the following terms, now you'll be able to actually tell

36:58 me what is the saturated solution, then what is unsaturated solution, then what is super saturated

37:06 solution, now then again number two is what is a solubility curve, so in our explanation of course,

37:13 in my explanation I gave you the definition you people should be able to define what a solubility

37:18 curve is, all right, thanks for watching, my name is Charles Christopher, till next time.