Hello everyone, today you're gonna learn with me, Ajaan Acharawadee Pansanit. Okay, I will teach you in the topic of chemicals and cosmetics. In the first chapter, I will introduce you to know about the water chemistry.
When we talk about water, what is water? In this content, we'll consist of the atoms and their valence electrons that involve in water, and the win-win approach in chemical bonding of water. The third one, we're gonna learn about water structure and their networking. The fourth one is unique property of water that involve in the high boiling points and pH value.
And the second one is the light disorbitant habit. And the last one on this topic, we will learn about emulsification in making skincare products from water. For the first content is atoms and their valence electron. If you see in this picture, The diamond and the carbon one, they are different in the pattern that you can see by your eye.
But if we look into the diagram, both of them are built up from the carbon element. The black color here is represents of the carbon one. But in diamond, the carbon linked to its order in the cubic shape. But for the carbon in the graphite one, they build together in the form of hexagonal.
So from this one, diamond and the graphite one, they are has the same black color of the carbon atom. What is the atom means? Atom is the smallest part of the matter that can exist. Both of diamond and graphite build up from carbon atom.
Both of them is similar in atoms. When we look into the atom of each element, atoms consisting of three substance. T3, the T3 inside. The first one is proton and the second one is neutron.
Both of proton in this one, the red color, and neutron in the blue color, they are the part of nucleus. And outside of the nucleus that spin around in this video, you're going to see the black color that's spinning is called electron. The electron will surrounding around the proton and neutron.
These three we call it three sub-particles proton, neutron and electron combine together and get up your atom. Okay, I forgot to mention protons is have the charge in positive charge that stay inside the part of nucleus. Neutron is neutral, no charge, it's zero. Proton is plus or positive.
For electron is negative one. So the negative one will surrounding or spinning around the nucleus which containing positive ion. So in each atom normally they will neutral charge. You're gonna see that. This one proton is positive and positive 2 positive 1 or 2 plus spinning with electron 2 electron with negative charge and is equal to 2 minus.
So 2 plus and 2 minus combine together you got 0 charge from this atom. Electrons that spinning around the nucleus can be found at different distance from the nucleus. You can see in this one is different nutrient. Hydrogen atom contains only one electron here and the electron quite near to nucleus of hydrogen atom. For helium containing two electrons that spin around, the distance is similar to hydrogen atom.
But for oxygen, you're gonna see this one's oxygen containing one, two, three, four, five, six, seven, and eight. Eight electrons, two electrons in size is similar distance with helium and hydrogen. But the other 6 electrons that are farther than these 2 electrons. For sodium atoms, electrons of sodium are higher amounts when compared with oxygen, helium or hydrogen.
The distance is farther. From this one, when we look into the level 1 or the layer that is nearest to the nucleus, The maximum value of electron that can fill up is only 2 electrons. E in this one is represent of electron.
And in level 2, the second layer here, the maximum value of electron is egg number. From this one, when electrons fill in the maximum value in level 1 and level 2 equal to 2 and x it will stabilize is each atom will stable so we call this one is octet rule each atoms required to fulfill in the maximum number of electrons okay and the ones At the most farthest, in this the one is mean electron. Electron at the most farthest from the nucleus is are called the valence electron.
From here, you're gonna see that the yellow arrow of hydrogen is the farthest one, is only one electron. Helium, the farthest one is two electrons. Oxytens The fastest one is six electrons.
And sodium, the fastest one is only one electron. From here, it is counted as valence electron. Hydrogen contains one valence electron. Helium contains two valence electrons. Oxygen contains 6 valence electrons and sodium contains 1 valence electron.
These valence electrons will link with the octet rule. How is it linked with the octet rule? As I told you in the previous slide, October As the adopted rules, atoms required to fulfill in the level 1 and level 2 add to an egg number. So, the carbon, helium and hydrogen in these 3 atoms.
Hydrogen contains only one valence electron in level 1. so From this one, helium contains 2 valence electrons and carbon contains 4 valence electrons. What happens? The yellow one, yellow arrow here is level 1. Maximum number of the valence electron is 2. Okay, so hydrogen, it can add one more electron here to complete the octet rule. But for helium, it's complete by their cells. For carbon one, here it has four valence electrons.
Carbon needs four more electrons to complete in the egg number in level two. From this, hydrogen and carbon are not stable. It's not complete in octet rule. Different from helium that is stable by itself.
From this one, it makes helium or the outer element in the same group with helium that complete octet rule. has the property to be inert. Sometimes we call it inert. inert gas okay but when atom is not stable it's not complete the octet rule what happened hydrogen atom in the blue color contains only one blue valence electron and hydrogen in red color contains only one red valence electron from this the blue color requires one more electron and the left counter requires one more electron.
So from these two atoms they can share electrons to each other that we call it share VE. VE is represent of valence electron. When it's shared to each other the thing that occur from this sharing electron is Bonding, we call it chemical bonding.
The bonding is represented by using that line in the middle between two atoms. Hydrogen blue color and hydrogen red color. Binding the chemical bonding together. Oh, from this one you can write in the shorter time to be H2 number in the subscribe here.
to represent hydrogen two atom bonding is altered. The chemical bonding that occur from the sharing of valence electron we call it covalence bonding. Co is mean collaborate okay and valence is valence electron.
The bond that occur from the sharing of valence electron we call it covalent bonding For this one, come to our ingredients, sorry, our molecules, water or H2O. The H2O, hydrogen atom, contains one valent electron. One valent electron.
Require one more for sharing. Okay. Oxygen one. contains six valence electrons.
Oxygen requires two more valence electrons to complete the octet rule. So this one oxygen atom will share its valence electron with two hydrogen atoms. From here, if you count the valence electron of oxygen now, it will be one, two, three four five six and seven and x okay if you count the hydrogen atom the valence electron of each hydrogen will be one and two one and two okay from this the one pair of valence electron that sharing use the deadline for represents of covalent bond And what happens when these four valence electrons that are not sharing, we call it unshared valence electrons, or called the other name is lone pair of electrons.
The number of lone pair, don't be confused. This pair is not meaning two, okay? The lone pair electron.
When I ask you, In the quiz or in examination, the lone pair electron of oxygen will equal to 4. 1, 2, 3 and 4. So this one oxygen has 4 lone pair electrons. The next one, the structure, from this the lone pair electron, from the previous one you know that electron has a negative charge. You're gonna see that represent of negative one and negative one.
Okay and the negative one make this the oxygen area turn to negative dipole. Moreover, the property of oxygen. Oxygen is the atom that has the property that highly strong to pull electron from the outer element that bonding. You're gonna see this arrow that electron from hydrogen will pool by oxygen.
When it's pooled by oxygen, making these two hydrogen atoms turn to partial positive charge. From this one, make the water molecule contain both of negative and positive in their structure. it that this one makes the water structure is polar.
The property main one is polarity. When it has both of positive and negative, the water and water molecules that stay together can make the bonding between the molecules that we call intermolecular bonding. In this one, the arrow shows the intramolecular, different one.
The intermolecular bonding is that line here. The intermolecular bonding occurs between the positive ion of hydrogen atom bonding with negative ion of oxygen atom from the outer molecule. The bond that occurs here, the intermolecular bonding like this, It has a specific name that called hydrogen bonding.
Okay, hydrogen bonding. The water molecule will binding like this together. Okay, when it's binding like this, making water is have different pattern. If you remember diamond and graphite, diamond and graphite make up from atom of carbon but different binding. The same thing ice and liquid water they create from the same water molecule and that line is represent of the same hydrogen bonding but in this one the hydrogen bonding that binding to each other is different distance.
In ice the hydrogen bonding will bind very beautiful pattern and close the molecule of water to each order making i is stable hydrogen bonds okay and turn to be solid state but for liquid water the pattern is very very different not beautiful pattern or in thai we call space pattern From this, make the water binding like this, it becomes to liquid state. The shape or the hydrogen bonding can change based on the boiling point. The binding of this water when you increase the temperature. Water molecule will loss out from its water. The pattern here we call the step of the water loss out that evaporations or in Thai we call Kan Rahoi.
Okay, from this one. Evaporation is the heat that turn water in liquid to be vapor or in gas state. Not only the boiling point of water that very high. Everyone knows that boiling point of water equal to 100 degree Celsius.
Water has the other property that is pH value. The pH value of water come from the water molecule 2H2O. is can, actions, action what?
exchange the hydrogen atoms by exchange one dot you're gonna see this one move from the right hand side to the left hand side when it changes when it moves it moves in the form of H plus so two molecule of water oh sorry two molecule of water will turn to be h3o plus or because protonium ion and os minus or hydroxide ion okay In pure water, amounts of hydrogen ion and hydroxide ion will equal together. That equal to 10 to minus 7 mol per liter. From this concentration, we can measure and calculate the acidity of the water because H3O plus is the thing that represent of acidity.
The measurements of acidity we use as the PS scale that conform the calculation in this equation. PS equal to minus log the concentration of proton or hydronium ion that you know that it equal to 10 to minus 7. When you solve this equation, it will got the plus. pH 7 number.
This is the pH 7 that the neutral liquid should be. In the detect of the pH value, normally we use the thing that called indicator or universal indicator. The indicator will change their color based on the pH as you see in this picture. The pH lower than 7, it means the concentration of hydronium ion is higher than the concentration of hydroxide ion. That this hydroxide ion is represent of the basic property.
The data of pH will lower than 7 here. For the basic one, concentration of hydroxide ion will higher amount. Making the pH value is higher than 7, you're gonna see that the universal is changed to be the green or blue or purple color here. From this, I show you the pH scale of the routine things that we're gonna see.
Egg is basic, the life basic property. and The strong acid one is your gastric acid in your stomach. And sometimes, some example, milk is the slightly acidic property.
The water one, because it has the positive and negative charge, it has the polarity, so it can dissolve. The polarity one. Polarity of water make water is excellent solvent for the polar substance.
We call this property that light dissolve light habit. Solute and solvent. In Thai, solute is ตัวถูกละลายนะคะ.
Solvent is ตัวทำละลาย. and When solute and solvent combine together, we get solution. Solutions are สารละลาย . The detection of solute and solvent is depending on the amount. Solute will be small amount, solvent is higher amount.
When this soap is altered and turn to be the homogeneous mixture, We call it solution. From this, because of hydrogen and oxygen is have negative and positive charge. So when elements of the compound that contain both of positive and negative charge, as you see this one, potassium-choline, potassium is positive one, Choline is negative one, it's very easy to dissolve in water. The property to dissolve one, you're gonna see that molecule of water will surrounding around this positive and negative molecule. We call this action as hydrating.
Hydrate is mean water, so water will hydrating this molecule. In the contrast one, water cannot dissolve the non-polar solute, for example, oil you're gonna see that oil and water is separate in two layers forming heterogeneous mixture. If you want to mix water and oil to ease water, we require the specific one that called emulsifier. The example of emulsifier that we found in everyday life is surfactant or soap. Okay, not only surfactant or soap, You're gonna see the way to making emulsion.
For example, this one is sludge dressing. In this one is the basic knowledge for making the skincare product. For the sludge dressing, you're gonna see that it contains olive oil, oil once, and lemon juice.
The juice one is high amount of water. You see that Water and oil cannot dissolve its water, but in sludge dressing, it can mix together. From this recipe, which one should be emulsifier? Could you guess?
The emulsifier one is egg yolk. Egg yolk will act as emulsifier to mixing lemon juice and olive to be homogeneous mixture or sludge dressing that we eat. What is the structure that emulsifier should be? Because of water is have the polar property and oil is non-polar property, it cannot mix to each other.
So the emulsifier is the compounds that contain Both of the water soluble part and oil soluble part. The specific word of water soluble part we call is hydrophilic. Okay, hydrophilic. And the oil soluble part we call is hydrophobic one.
From this picture, which one should be hydrophilic and hydrophobic? The water soluble here is hydrophilic. You're gonna see it has a charge similar to water.
And oil has no charge here. We call it hydrophobic part. The molecule that contains both of water soluble and fat soluble we call it amphiphatic nature. In this, the amphiphatic nature make them possible to self-aggregate into a supramolecular structure that called micelle.
This one micelle thing is important in skincare product. What is it? The polar, the water soluble and oil soluble can making the form of micelle, this one, the circle one called micelle.
My cell will forming when this amphiphilic or emulsifier go to the water part the water part is polar so the water soluble will attack to the water outside and inside is oil, oil soluble will make it inside form the circle here that called my cell For the chapter 2, I will cut this presentation to be the author clip. We will make it not too long presentation. Sawasdee ka, see you in the next clip.