Characterize bonds between the two atoms as covalent or ionic. (a) Cl and F (b) Rb and F (c) Na and S (d) N and S

Video transcript

All right. Hi, everyone. So this question says to provide the chemical formula of a hydride formed by the combination of hydrogen. And the listed elements identify whether each hydride is ionic or coal. For part A, we have potassium and for part B, we have sulfur. Now recall that a hydride is a binary compound in which we have hydrogen as well as one other element. And so we can distinguish between ionic and covalent hydride by what the other element happens to be because ionic hydride form when there's a sharp difference in electronegativity between hydrogen and the other element. So in this case, right, hydrogen combines with a metal, specifically either an alkaline metal or an alkaline earth metal because of the difference in electronegativity, the metal ion loses an electron to hydrogen. Whereas by contrast, right, cohen hydride tend to be formed between hydrogen and a non metal because the difference between or the difference in electronegativity between a hydrogen and a non metal is not large enough to form an ionic bond. Rather for a covalent hydride. Hydrogen shares its electrons with the other atom to form a covalent bond. So now let's start off with part A which is with potassium. Now recalled potassium is a metal found in group one a of the periodic tape, meaning it is highly electro positives. So what that means is that the difference in electron negativity between potassium and hydrogen is going to be quite large, right? So therefore, potassium is going to lose want electron to become K plus whereas hydrogen gains that electron to become H minus. So now these ions that have opposite charges can combine together via electrostatic forces to form Kh or potassium hydrate. And it's worth noting that because this is an ionic compound, it should be neutral overall, right? So the positive one charge balances out the negative one charge. So for part a the chemical formula is kh which means that we have an ionic hydrate. So now lets consider part B because for part b this time, we're combining hydrogen with sulfur, which happens to be a non metal, right? So because sulfur and hydrogen are both non metals, the difference in electronegativity is less stark, right? So therefore, electrons are going to be shared between hydrogen and sulfur to create a covalent bond. Now, it's worth noting also that sulfur is in group six A of the periodic table, which means that it has six valence electrons. Now because it has six valence electrons, it requires two more to complete its octet, which means that in this case, sulfur is going to form two covalent bonds with two hydrogen apps, which means that my chemical formula is going to be H two S, right? Because the two chemical bonds are covalent bonds to each hydrogen, provide the remaining two electrons that sulfur needs for its octet. Because recall that if H two S only had one atom of hydrogen, then our sulfur atom would have two unpaired electrons. And recall it unpaired electrons are actually relatively unstable, which means its sulfur would rather create two covalent bonds instead making H two S a covalent hydro. And there you have it. Here is your answer for parts A and B. So with that being said, thank you so very much for watching. And I hope you found this helpful.