like their atomic and physical properties the chemical properties of transition elements are very different from those of the main group elements one being that transition metals have multiple oxidation States versus just one or two like we see with our main group elements okay so what are oxidation states and their rules we got to remember from kim11 the oxidation states are going to indicate the degree of oxidation or loss of electrons or reduction gain of electrons that an atom has undergone okay so there are specific rules that you can follow of course I kind of brought these kind of small rules from the Tyler to Wick group um also you can see rules from chapter 4.2 in your book it's all about helping us get those oxidation state numbers so that we can go further and use them in reduxx reactions if we'd like now we know what transition metals they love to again lose the NS electrons first like we just saw with the electron configuration okay so the most common oxidation state that we normally see with transition metals is going to be that plus two but again they can have multiple oxid States and multiple stable oxidation States all because of those incompletely filled de orbitals so it's all about the electron configuration and how many electrons are in those D orbitals and if they are filled or unfilled okay so if they're unfilled then they definitely have more abilities to be a part of reaction okay and then we do have this little table here that's going to be your oxidation States and then a different period for elements as you see here now when it comes to the first five elements here first five elements the maximum possible oxidation state is going to be related to the loss of all the 4S you got to lose all 4S and 3D electrons and so that means that if they have unpaired D electrons and all the s electrons are going to be lost that tells you the maximum oxidation state for these first five elements for examp okay of course you can look at other elements and their different oxidation States I just want to kind of clarify for those first five you also will see from this table most common which is most stable and less common Which is less stable which goes to show you that although transition metals have the ability to make higher oxidation compounds it doesn't mean that they will so for manganes for example it has a stable in plus seven plus 4 and plus two iron is usually plus two or three copper is usually uh one or two for example zinc is usually two so you kind of can see that a lot of these different transition metals um will have common oxidation states that we also will see in our compounds in the lab for example so just like some of those oxidation States gave us color which we talked about earlier we can use those oxidation state numbers to help us see what kind of colors different compounds would be and also again use them for different types of reactions and redox reaction now just to just briefly talk about oxidation state rules it's just like for example if you have an element that's by itself like say you have O2 let write over here O2 the oxidation number would be zero if you anything that's Elemental will be a zero oxidation number and so it's just little rules like that that you definitely have to go back and review and so although this is a flashcard moment you can go back and just add little details to your flash card like hey what is oxidation rules let me go back and add a flash card about that for examp let's go ahead and see this in practice and use this as our chance to review instead of just me just jumping in let's go ahead and use it in practice do our best to understand andent so for our example here the first one it says determine the oxidation state of cobalt and Co br2 so we're looking for this transmission metal Cobalt what the oxidation state of zinc and ZN CO3 and also what is the oxidation state of silver and ag2s so the first thing that we want to do is just make sure that we are using the rules for the oxidation numbers what we can do is go ahead and use these rules whichever kind of way you remember them to help us figure out the oxidation numbers of elements that we know in the overall compound once we have elements that we know in the overall compound we can use that to help us solve for a variable of what we don't know okay so for example with cbr2 here we know that bromine is going to be a hallogen and halogens usually have a minus1 charge so we can automatically say that this has the oxidation number of minus one we also know that this entire compound is neutral so this entire compound is equal to zero now when you have compounds that have a charge attached to it you have to make sure that you set your compound equal to zero when you're doing these type of exam okay and I'll give another one of those later on okay you see I have added this compound here M4 minus so that means this compound actually have a charge so you would have to set this whole entire thing equal to minus one okay now again cbr2 BR is going to be minus one this whole thing is said equal do you're going to go through and make sure I figure out all the different elements that I know a charge for to help me figure out what I don't know the Char so um let's go ahead and look at this DN CO3 so a lot of folks will look at this and say okay there's three separate elements we remember our CO3 is actually the carbonate polyatomic ion so it is going to be a two minus charge and so anything I already has a charge um then we can basically just use that to our advantage for oxidation numbers this whole thing is equal to two Okay and then for ag2s we know that sulfur is in the same group as oxygen so if oxygen is usually minus two then sulfur usually going to have a minus two um oxidation number as well and this whole thing is equal to zero now down here we know our oxygen is normally going to be minus two unless it's attached to some like kind some kind of like um exceptions but it's not attached to any peroxid so we don't have to worry about that it's just attached to manganese and this whole thing is going to be equal to minus one so again you're just kind of locating where things are as far as you understanding where they are in your oxidation rules okay and then you want to just focus on what you want to set everything equal to whether it's a neutral compound or not make sure you can identify polyatomic ions and then all you have to do is just use algebra to find out what you don't know or your answer so let's go ahead and get into that but for example back up to co br2 because we don't know what Co is we can set that as X now we're going to add that to what we do know so there's two BRS what's the charge of BR minus one this entire thing is equal to zero so we have x - 2 is equal to0 add two to both sides therefore X is equal to + 2 so that means our Co is equal to a plus two oxidation number in order to be a part of this compound this neutral overall compound let's continue on with the ZN CO3 so again we already said that our carbonate is going to be minus 2 here so we would just go ahead and that to our advantage let's go ahead and do our math we're trying to find zinc so that's going to be our X added to our carbonate there's only one of them that has a minus two charge and this whole thing is equal to zero so x - 2 is equal to zero going to add two to both sides x equal to + 2 for our zinc great now let's continue on the different color here so we are looking for our silver again we know that our silver is going to be X but but there's two of them so we have 2X + 1 * a min-2 charge for the sulfur is equal to Z so 2x - 2 is equal to Z okay so we're going to add two to both sides 2x is equal to 2 divide to by U to both sides my X is going to equal to + one and so now um my silver is therefore going to equal to plus one oxidation number then finally let's do the one down here okay so we're looking for our manganese which we're going to set for X we have four oxygens that each have a minus two charge and this entire thing is equal to minus one so we're going to have x - 8 is equal to min-1 add eight to both sides my X is equal to+ 7 so my manganese is going to have a plus seven charge or sorry oxidation okay all right folks and so this is how you want to kind of approach oxidation number you'll see oxidation number and electron configuration as a main type of examples for your homework so it's just again there to help you practice if you don't understand come back to this video if you don't understand even smaller details you want to go back and review oneone information all right folks