Give an example of an ionic carbide. What is the oxidation state of carbon in this substance?

Video transcript

Alright. Hi, everyone. So this question is asking us, what is the oxidation state of carbon in SRC two is SRC two, an ionic carbide. Now, here we've got four different answer choices. Each proposing a different oxidation state or carbon and each proposing whether or not it is or is not an ionic carbide. So let's start with first finding the oxidation state of carbon. Now, what you'll notice is that carbon in this case is connected to strontium, which happens to be a metal existing in group two A or the second column of the periodic table. Therefore, right, the oxidation state of strontium is going to be fixed at a positive two. So we can use this to find the oxidation state of carbon, which happens to be our unknown because recall that the sum total of all oxidation states of each atom has to equal the charge of the compound itself, which in this case happens to be zero, right? So if I go ahead and I take the oxidation state of my one atom of strontium, and I add that to the oxidation state of carbon multiplied by two because I have two carbon atoms that should give me a total of zero. So in my equation here, I can go ahead and substitute plus two or the oxidation state of strontium. And so when I subtract both sides by two, I get the two multiplied by the oxidation state of carbon is equal to negative two. So now when I divide both sides by two, I get that the oxidation state of carbon is equal to negative one. So my answer here is that the oxidation state of carbon is in SRC two is going to be minus one or negative one. I should say. Now recall that because the oxidation state of carbon in this compound happens to be negative, it can be classified as a carbide. But we can further specify what type of carbon we happen to be dealing with in this case, right? Because recall that we have ionic carys, we have interstitial carbides and we also have covalent carbides. Now, the main difference between these three subcategories is what type of atom are carbide, meeting our carbon with our negative oxidation state. It's connected to, right. So, ionic carbides involve the combination of a main group medal with the carbide itself. Whereas interstitial carbides feature a transition metal in addition to our car, but now COVID and carbides are different from both ionic and interstitial carbides in that they involve another nonmetal combining with our carbide. Now, as we discussed previously, strontium happens to be a medal that resides in group two a of the periodic table. Therefore, it's actually considered to be a main group medal, which means that SRC two is an ionic carbide because we do have a main group metal combining with our carbide. So our answer here is going to be option B in the multiple choice because the oxidation state of carbon in SRC two is negative one and SRC two is an ionic carbide. So with that being said, thank you so very much for watching and I hope you found this helpful.