hello everybody welcome back to med school eu my name is andre and today we're going to be doing another educational video on chemistry from the imat specifications today the topic will be inorganic compounds and we're going to take a look at their properties more specifically the properties of oxides hydroxides and acids let's begin talking about oxides and what they are and their properties well oxides are defined to be chemical compounds with one or more oxygen atoms and they will typically be binary compounds and binary compounds are basically when you have two different elements involved so you've got some sort of element whether a metal or a non-metal and an oxide so binary meaning that you have two things one and two combined together in one compound now some examples of oxides would be lithium oxide li2o carbon dioxide sulfur dioxide we have calcium oxide or water h2o these are all oxides because they simply contain an oxygen atom in them now because they contain this oxygen atom they will be called oxides and they will exhibit specific properties one of the most important things that we have to know about oxides for the exam is we have to know which oxides are acidic in nature which oxides are basic in nature which oxides are amphoteric in nature and which oxides would be neutral in nature let's first discuss the properties of acidic oxides they're also commonly known as acid anhydrides now they will follow a general equation scheme or chemical equation scheme of non-metal oxide that will bond with water so non-metal oxide dropped in water will result in an acid this is how acids would be formed so as an example we could use so2 right non-metal sulfur is a non-metal oxygen is a non-metal so it's a non-metal oxide and water is going to form sulfurous acid so h2so3 this is called sulfurous acid and if you are wondering how i just came up with the name sulfurous acid you should check out the video right up here at the top uh to learn inorganic nomenclature now when i take this um sulfur dioxide so2 and i'm going to combine it with a base so something like naoh then the result is going to be a salt and water so na2so3 and water so this forms salt and water whenever we have this type of arrangement we know that this is going to act as an acid and this will act as a base and because the general neutralization reaction is acid plus base that results in water and salt so when this occurs you know that you're dealing with an acidic oxide so non-metal oxides will make an acid and they will be acidic in water moving on to basic oxides commonly known as base anhydrides so metal oxides are going to be the ones that will form bases when dropped in water so metal oxide plus water will form a base for example if we have magnesium oxide mgo plus water we know that we are going to form mg oh2 so metal oxides are generally going to be the metals that will bond with oxygen from groups one and group two so your alkali metals and alkali earth metals are going to be the ones that will exhibit these properties now when we're reacting them with acids so when you have a metal oxide that will react with acid it will again form a salt and water and the reason for that is uh again because this is just a neutralization reaction since metal oxide is going to act like a base now let's talk about amphoteric oxides and the word amphoteric means substance that can react as an acid or a base in order to really know what this means we also have to know what is an acid and what is a base so this is also going to cover that part of the specifications where it talks about acids and their properties so uh to identify what is an acid and what is a base it's there are two specific definitions for that so we're going to learn about those definitions first and then we're going to circle back to the amphoteric oxides to cover some examples first we will discuss the arrhenius definition of acid and bases so according to the arrhenius definition an acid is going to be a substance that produces a proton or a hydronium h3o plus hydronium a compound in aqueous solution and the definition of a base according to arrhenius is uh some sort of compound that produces hydroxide ions in aqueous solutions now arrhenius definition is no longer used in modern science so instead we came up with a different definition called the brown bronsted lowry definition so let's talk about that one next so the brussel lowry definition is a little bit simpler than that so an acid according to these scientists is going to be a proton donor and bases so a base is going to ident be identified as a proton acceptor now that we know the two definitions and these ones are the ones that are typically used to this day we can now establish what is an amphoteric oxide since it can be both acid and a base so for example if we have an acid hcl and water in this case the water will be in a situation where it will have to act like a base so what we're going to produce is h3o plus and cl minus so in this case this would be the acid and water will have to be the base and it's the base because it's going to accept the proton as you can see the water accepts a proton whereas the acid donates a proton and now is left with just the cl minus now in a different scenario of nh3 for example that will react with water we are going to get nh4 plus ammonium and hydroxide ion so in this case as you can see the water is going to be donating a proton so it's going to act like an acid and of course nh3 is a base so when it acts like an acid it's going to get rid of a proton and will remain as an oh minus whereas the nh3 the base will now accept a proton next let's talk about hydroxides and i mean hydroxides is is the oh uh minus so we've already discussed this in in multiple formats so hydroxides are essentially going to be forming bases so they form bases when they react with metals and some of the strongest bases that will be formed is when the o h reacts with an alkali metal so as an example of some alkali metals that form strong bases going to be sodium naoh is a strong base lioh has a strong base koh has a strong base and so on so there's going to be six strong bases and most of them will be formed from the alkali metals now a couple of properties of hydroxides since they are going to exhibit bases uh they're gonna be they're going to taste bitter so bases taste better they're going to feel slippery so if you ever grab detergent detergent is a base it's a classic base it's a strong base as well in most cases so if you grab detergent you put on your hands it's slippery and if you taste it it's bitter which i don't recommend and of course some of the most notable properties which we already discussed is that it causes a neutralization reaction um with acid so it neutralizes acids now since we already talked about acids and some of their properties and what is the definition of acids we could here talk a little bit more about their properties briefly so acids are going to be based on the formation of hydronium and proton ions and essentially they are going to taste sour rather than bitter like bases another notable property is it's going to dissolve metals and release h to gas and of course they're going to neutralize bases another concept that we do have to know about acids and bases is going to be ph and ph is going to be the measurement of the concentration of h plus ion inside the aqueous solution so the more ion you have the closer it is going to be to zero the more proton you have the closer it's to zero and the less proton you have the closer it is to 14. so 14 is going to be categorized as a base and closer to zero is going to be categorized as an acid and the closer it goes to zero the stronger the acid the closer it goes to 14 the stronger the base and exactly in the middle at seven we're going to have a neutral compound so for example something like like we talked about with the carbon monoxide or even water water is amphoteric yes it has the property to be both but if water is just on its own it's going to be neutral at ph 7 if it's purified water of course this concludes our lecture for today click on the next video to learn more about the properties of acids and salts [Music] you