Here we go. This is the second chapter, Elements and Compounds. Okay, so in this chapter, basically we're going to be talking about generally naming compounds.
All right, so let's go to the first part here. So you have something called Elements and Compounds. If you look at the periodic table, okay, let me see whether there's a periodic table here.
I think there should be one, no? Okay, now if you look at the periodic table, right, everything that you see on the periodic table, these are all called elements. okay everything here are elements so every there are what 118 here 118 can you see here so all of these are classified as elements right up to here so every single thing is an element so that's first thing now the other thing which is called elements are all okay okay all all molecules okay all molecules you which are made up of the same atoms okay all molecules which are made up the same atoms so like for example let's say oxygen hydrogen chlorine bromine iodine, ozone, okay.
Anything else that you can think of which is like this, all right. These are all classified, okay, I say like fluorine. All of these are classified as elements as well, okay. So first thing is all this on the periodic table, everything is an element and all molecules, all molecules which are made up of the same atom. So these are all classified as elements, okay.
Now if you look at the periodic table here very quickly or everything which is is in blue are metals everything which is in green are non-metals so you you notice that there are more metals than non-metals meanwhile the ones in the yellow here are called metalloids metalloids have characteristics which are some characteristics like metals like for example they have high melting points they might conduct electricity but then they have other properties of non-metals like for example when they make compounds they make covalent compounds generally all right So their compounds are more covalent, not ionic or not metallic. All right. So that's one. So this first part here was talking about elements and compounds. So what are elements?
Elements are everything that you see on the payroll table and including all of the molecules which are made up of the same atom. Okay. So these are all considered as elements.
Okay. So naming compounds. Now, you see this word here. Don't get confused or don't get panicked with this word. Binary.
Binary. binary ionic compound. Now what does binary ionic compound means? It basically means ionic compounds, okay, ionic compounds made up only, only of two types of elements.
Only two types of elements. Okay, you see look over here, right? Look over here potassium fluoride So it's potassium fluoride. Potassium fluoride is only made up of two elements. The first element is potassium.
Second element is fluoride So if you look at this Sodium nitrite the first element is sodium and the second element is nitrogen So only two elements look at this one calcium phosphide is made up of It's made up of one calcium and one phosphide. That's it only two different types of elements. So this is called a binary.
So binary means bi means two. And then another example here is magnesium sulfide. So when you look at the names of binary ionic compounds, if you look at the names of the binary ionic compounds, the first name that you see is the name of the metal.
In every case, it's the name of the metal. See here? Thank you. is the name of the metal so this is taken directly from the periodic table meanwhile second the second word has this addition here ide okay fluoride fluorine becomes fluoride nitrogen becomes nitrite phosphorus becomes phosphite sulfur becomes sulfide so you keep adding this i'd here can you see here so it says here okay the the The N-ion has an ending of the element name has been changed to ide.
Okay, it's been changed to aid. So the first word is always the name of the metal and the second word is the name of the non-metal. So if we look at this right if we look at this potassium fluoride what we can do is we can separate potassium fluoride we can separate potassium fluoride that's a potassium fluoride right we can separate it into potassium ion and fluoride ion okay.
In the case of this it is actually you can separate this okay this is you can separate sodium nitride you can break this up into sodium and then nitrite okay when you break it up in this case you get calcium and then phosphate right so you can break this up into calcium and phosphate Here magnesium sulfide, magnesium sulfide you can break it up into magnesium and sulfide. So these are the names of binary ionic compounds. So when you hear the word binary ionic compounds you just need to know it is made up of only two types of elements that's what it is okay. So then you come to this one.
here that talks about polyatomic ions. Now poly basically means this word basically means many. Okay. It means many. So this whole sentence here, this whole sentence here basically means ions which are made by the Up of many.
atoms. That's what this whole polyatomic ion basically means. All right. So an ionic compound, in ionic compounds, either one or both of the ions could be polyatomic.
A polyatomic ion is an ion composed of more than one atom. Okay. More than one atom.
So if you look at here. Okay. So look at this.
Look at this here. So it's made up of more than one type of atom. So there are five different types of atoms.
So this is a polyatomic ion. So other examples of polyatomic ion is this one here. This is also a polyatomic ion.
Okay polyatomic ion. So it's an ion. It's an ion which is made up of many atoms.
Okay made up of many atoms. Not many types of atoms necessarily but many atoms. Okay. So these are called polyatomic ions. So there are many polyatomic ions.
You can see some examples here. They are made up of many different types of atoms. These are all examples of polyatomic, except for this, you see, this is only made up of one. This is one.
this is not polyatomic this is also not polyatomic because it's only one it's only made up of itself right the rest are can be considered as polyatomic ions all right um okay so the definition here you can see here a polyatomic ion you is an ion composed of more than one atom. More than one atom. So if you look at this by that definition these two do not fit the criteria. It must be made up of more than one atom okay. So this is not polyatomic.
Okay, do you need to memorize this? If you can memorize it, it's good. It'll be helpful for you, okay? So these are some examples of cations.
These are all cations with charge of plus one, like hydrogen, ammonia. silver, copper. I mean there are others that you can you can memorize if you want to like for example sodium, potassium, then there is calcium, there is magnesium but there are so many for you to memorize so I guess don't really waste your time memorizing but it'll be good if you can kind of know the names of the ions okay. All right so when we come to naming ionic compounds okay this is example of ionic compounds if you look over here lithium hydroxide so if you know the formula for hydroxide lithium so usually when we name ionic compounds right let's say for example you have a let's say you have a positive ion a m plus and then you got b n minus okay so if you remember from high school a n b m okay if if if n equals to m then Thank you.
Then it is just AB. Okay. Then it's just AB. So if N equals to M.
All right. Then it's just AB. So that's what it means here. So you see like for example.
Okay. There's no example. Okay.
I look at that. This is an example. So lithium is positive one.
Hydroxide is negative one. So it is just LiOH. Okay. That's it.
So in the case of calcium chloride, what happens is you see calcium. Chloride. Am I right? So what happens is this two goes over here and this one comes over here.
So it becomes calcium Chloride. Two goes there. Okay, we don't put the one.
So this is how positive ions are combined together. If you look at ammonium carbonate, if you look at ammonium carbonate here, right, you can see ammonium Then you have carbonate. So what happens is this two, this two comes over here.
So it becomes ammonium bracket to carbonate. So what does this mean? It means that this two, this two belongs belongs to ammonium.
Okay. So that is why we put a bracket and we put a 2 here. All right. Okay. So then that brings us to binary covalent compound.
Again, the word binary means covalent compounds. Okay. Covalent compounds. Made up of only two different atoms.
That's what it means. Okay. Made up of only two different atoms. That's what a binary covalent compound is. So the word binary means two.
Binary basically means two. Okay. So let's look at some examples here.
So these prefixes we will. it'll be important for us to know like like mono di tri okay so here comes the naming look at this example here okay so all of these are examples of binary covalent compound so again i repeat binary means it's just made up of two elements one two okay see every case is just two different types only okay so that's why we call it binary covalent compound okay let's look at the naming process when we do the naming process right the first name is the name of the first element you see nitrogen first element is nitrogen first element is phosphorus first element is sulfur first element is chlorine okay then what we do is we use this prefix here see this prefix monoditrite tetra and so on and then we put it in front here you see you see but okay listen very carefully if the first element the first element is single we do not do this we don't say we do not say mononitrogen mono oxide. Okay, we do not say this. This is wrong. We do not say this.
This is wrong. If the first element is single, we just leave it as it is. You see, like for example here, there's only one phosphorus. So we don't say monophosphorus. We just say phosphorus.
Okay, but but if you see if the second element is single Okay, like say like in this example here, right? See the second element is single So we use the word more no to tell to tell everybody that the second and element is single. The first element single means we don't say anything.
If the second element is single, then we use the word mono. So like in this case, this was di, di nitrogen. There are two of them, mono oxide. In this case, phosphorus, we don't say monophosphorus, we say pentachloride. Penta means, what does penta mean?
Here you see, penta means five. So pentachloride. Disulfur, two sulfurs, dichloride.
Okay, dichloride. So what again if you notice what we are doing here is we are adding this ide at the back here ide ide ide ide okay. So this is dichlorine hepta hepta means seven oxide hepta. So basically you are telling people there are two chlorines and there are seven oxygens dichlorine di sorry dichlorine hepta oxide okay.
So note it says here it is accepted by IUPAC. IUPAC is the International Union of Pure and Applied Chemists. You can decide to write monoxide or monoxide, whichever. You can put double O's there or single O's. That's not meta, okay?
Okay, so, um, okay, so, all right. that we done here very quickly let's come to the last part here naming assets okay so again there are some assets that you might need to know the naming process okay so there are some assets here so binary asset again the word binary means binary means 2. Whenever you talk about acids, one of the elements is always hydrogen. So one element is always hydrogen.
So when you say binary acids, one element is already hydrogen. So we're just talking about what is the second element. So if you look at examples here, Binary acid could be like HCl and then HBr.
Anything else? Okay, let's say HF. These are examples of binary acids.
That means they are acids which are only made up of one hydrogen. Okay. Okay, so this is hydrochloric acid.
Now, you see, if it is HCl liquid, then we call this hydrogen, hydrogen chloric. We call this hydrogen chloric. If it's HCl aqueous, then we call this hydrochloric acid okay we call this hydrochloric acid. So the difference between liquid and aqueous. Aqueous means hydrochloric acid if it's liquid is hydrogen chloride okay just like HBR liquid this is called hydrogen bromine but if it's HBR aqueous then we call this Hydrochromic acid.
Hydrochromic acid. That's the name. Alright, so then that brings us to this part here. It talks about oxy acids.
Oxy acids are also known as oxo acids. Okay, acids. Oxo, sorry, typo. oxy acids are also called oxo acids so oxo basically or oxy basically means there is oxygen in the acid so look at these acids here right this is nitric acid you look at nitric acid there is oxygen in nitric acid so nitric acid is an oxo acid sulfuric acid so sulfuric acid has oxygen in it is called an oxo acid then there's carbonic acid there's phosphoric acid these are examples So if you look at here just very quickly this was nitric acid and then we have something called nitrous acid. Nitric acid has one oxygen, nitrous acid has one oxygen less sorry.
Nitric acid has three oxygens, nitrous acid has two oxygens. Same thing with sulfuric acid H2SO4 versus H2SO3. This is sulfurous acid, sulfuric acid. So you need to know the name here. Sulfuric acid and the other one was sulfuric.
Ic is four, us is three. Okay and the very very last part okay very very last part here it talks about hydrated compounds okay hydrated compounds so hydrated compounds are like this compound here you see this this is called so you see this dot sorry if you see this dot over here so this basically means it is a hydrated copper this is called copper 2 sulfate pentahydrate pentahydrate hydrate basically refers to water okay. So what does this dot mean?
What does this dot mean? So if you imagine, if you imagine copper sulphate to be a solid like this, right, if you imagine, so water, there are five water molecules which are physically attached. to the surface of copper sulphate, physically attached. Just like when you shower, there is water which is attached to the surface of your body. When you use a towel, you can wipe it off.
So this water is physically attached to the surface of copper sulphate. Alright, so let's say this is copper sulphate. So what you do is, if you heat this up, just like you when you go and shower, if you go and stand under the sunlight, the water can evaporate. So what will happen is, the copper sulphate will evaporate. will remain dry and then all of the water will be evaporated.
So this is what it means by this dot here is called hydrate. So there are many others like for example If you look here, this is called sodium carbonate 10 10. What is 10? 10 is called deca you see here 10 is called deca deca hydrate.
So This is called sodium carbonate deca hydrate. All right. So this is this part here on the types of compounds types of compounds so so basically You can see that this is the Basically, unfortunately for you, you might want to spend a little bit time memorizing these things.
What I would suggest is you might also want to work out on some of the guided learning or revision questions. All right.