What is the systematic name for each of the following ions?

(a) [MnCl₄]^2-

(b) [Ni(NH₃)₆]²⁺

Video transcript

All right. Hi, everyone. So for this question, let's give the systematic names for one PD H2O 64 positive and two mobr 42 negative, which are complex ions. Here we have four different answer choices, proposing different names for both complex ions. Now recall that a complex ion is one component of a co-ordination compound that's composed of a metal cion in the center as well as multiple or at least one molecule or ion attached to the metal center referred to as legates. Now, when it comes to naming a complex ion, all ligands are listed in alphabetical order before the actual name of the metal ion itself. So if we start with the first complex part one here, that is PD H2O 64 positive. So for the first part, right, the first thing I like to do is go ahead and start by naming my ligands in alphabetical order. Now, it just so happens in this case that we only have one type of ligand, which happens to be H2O no h2o of course is water. But when naming water as a ligand, we call that aqua. So in the actual name of the complex ion a water molecule as a lichen would be described as aqua. Now, in addition to naming the ligand itself, recall that prefixes are necessary to indicate how many of each type of ligand is present in the complex. Now, exceptions do apply for ligands that are poly dentate, meaning they have multiple sites of attachment to the central metal atom. So when it comes to poly dentate ligands, the specific prefixes that are used are slightly different. For example, we use bis ri et cetera. But for mono dentate leggings like our aqua leg in here, because we have six of them present in the complex. For part one, the prefix is hex. So thats hex aqua. So now we go ahead and proceed with naming our middle center. Now, our metal center is PD which references palladium and recall that the name of the metal can actually change depending on the charge of the overall complex. However, notice here that the overall complex is a cion with a charge of positive four, this means that the metal's name does not actually change in this case. So because the name of the metal center is palladium in the name of the actual complex, that name is not going to change because it is a cion, right. So after the phrase hex aqua described by lagoons goes the word palladium with no spaces in between. So now because palladium is a transition metal, there has to be a Roman numeral in parentheses after the metal's name to specify its oxidation state. So here recall that the oxidation states of the metal center and all ligands must equal the overall charge of the complex because the overall charge is synonymous with the overall oxidation state, right? So if the oxidation state of palladium is X, then X added to the oxidation state of our aqualad multiplied by their quantity must equal positive four. So in this case, recall that aqua ligands happen to be neutral, meaning they have an oxidation state of zero. So X added to zero equals positive four, which means that X is equal to positive four. So in the actual name of the complex, after palladium should be a roman numeral four in parenthesis, which means that the name of our first complex ion is hex aqua palladium four. So now if I scroll down here to open up some space, we can proceeded with the second complex ion which happens to be Mobr oops mobr four two negative. So in this case, notice how the overall charge of the complex ion is negative. So that's going to slightly affect the rules that we discussed earlier when it came to naming right, starting off with our ligands, we only have one type of ligand, which happens to be BR negative of which there are four, right. So recall that the name of the ion BR negative one is bromide. However, the name somewhat changes because of the fact that it is a ligand and it is an ionic, right, instead of referring to it as bromide in our systematic name, the suffix ID E gets dropped entirely and replaced with O. So we go from bromide to bromo and of course, this is a mono dentate ligand. So we're going to use the appropriate prefix to describe how many of them there are. In this case, there are four, which means that the appropriate prefix is tetra. So after all ligands have been listed right, with the appropriate prefix for their quantity goes the name of the metal center which according to the symbol mo happens to be mo lived in a. However, recall that this is an anionic complex ion. So the name of the metal is going to change right? When the complex ion has an overall negative charge, the metals name ends with the suffix A te. So the final portion of the metal's name in this case, the E and um of molybdenum get replaced with a te. So we go from molybdenum to mole date. So because molybdenum is also a transition metal, we have to specify its oxidation state in this complex. So if the oxidation state of molybdenum is thanks again, right X added to the total oxidation state of all bromo ligands must equal the overall charge which is negative too. So our promo ligands are anionic with a charge of negative one each, which means that the oxidation state is also going to be negative one. So that's X plus or added to negative one multiplied by four equals negative two. This simplifies my expression to X subtracted by four equals negative two. Which means at X after I add both sides by four equals positive two, this means that the oxidation state of molybdenum in the second complex ion is positive too, which means that after the name mole date goes a Roman numeral two in parentheses and there you have it. So if I scroll up here to the very beginning to see our answer choices, our answer is going to be option a in the multiple choice because the systematic name of the first complex ion was hex aqua palladium four. And for the second complex ion, it was tetro bromo moli date two. So with that being said, thank you so very much for watching. And I hope you found this helpful.