Locate sulfur, selenium, chlorine, and bromine in the periodic table: (a) Which binary acid 1H2S, H2Se, HCl, or HBr2 is the strongest? Which is the weakest? Explain.

Video transcript

welcome back everyone among hydrogen to deuterium hydrogen cell inside our scene and antimony hydride. What is the strongest binary acid and which is the weakest. We need to explain why. So we're going to begin by first recalling the fact that as our polarity increases of the bond between our acidic hydrogen and the atom bonded to our acidic hydrogen which we'll call X. As this polarity relationship increases in this bond. This is related to an increase in acid strength and we would represent our asset as H. Sub in X. Next we want to focus on the atoms that are acidic atoms sorry are acidic hydrogen are bonded to. We have to Laurie um selenium arsenic and antimony and recognize that on our periodic table these atoms are located in the P block. Specifically we want to focus on groups five A. And six A. Across periods four and five where in group five A. Across period four we would find arsenic underneath arsenic. In period five we would find antimony. So this isn't us here, next to antimony in group six A. We would find to Laurie um and above to lori. Um across period for we would find selenium. So the next thing we want to recall is our trends on our periodic table. First beginning with electro negativity, since that gives us an idea of the polarity of these given acids. So we have in the top right direction an increase in electro negativity on our periodic table. And then our second trend we would recall is our trend for atomic radius, which increases towards the bottom left of the periodic table. So with these two trends outlined, We can first confirm the fact that selenium would be the smallest adam. However based on electro negativity, it's the most electro negative. And because it's the most electro negative atom, we would say therefore its bond with the acidic hydrogen is extremely polar, especially because this atom is small. And so our hydrogen cell inside is the strongest binary acid. That's our first answer. And now we need the weakest. So we want to find a larger but the least polar. Or sorry, the least electro negative atom which would therefore give us the least polar bond with the aesthetic hydrogen. And we would see that the least electro negative atom out of the given would be antimony. And so we would confirm that antimony hydride is the largest autumn with the least electro negative or sorry, electro negativity. And therefore antimony hydride is the weakest binary acid. And this would be our second answer. And how we explained why these answers are true is again because selenium is the most electro negative and therefore its bond with the acidic hydrogen is going to be extremely polar. Thus the electrons will be more closely attracted to our selenium atom and the hydrogen will be inclined to become a proton. So the the molecule will disassociate easily. Whereas antimony hydride is the least electro negative. Specifically antimony is the least electro negative and therefore it forms the least polar binary acid where the electrons in the bond that antimony shares with the hydrogen form an electron cloud with higher repulsion, especially since we see that antimony has such a large atomic radius. And so the bond that antimony shares with the acidic protons or with the acidic hydrogen are weaker and these hydrogen are going to want to hold onto the electrons in the bond that it shares so they would be less inclined to become protons. So for our final answers, what we have highlighted in yellow would be our correct answers. I hope that everything I reviewed was clear. If you have any questions, please leave them down below and I'll see everyone in the next practice video.