Skip to main content
Ch.16 - Aqueous Equilibria: Acids & Bases

Chapter 16, Problem 4

Which is the strongest acid? (LO 16.4) (a) HClO3 (b) HBrO3 (c) H2SO3 (d) H2TeO3

Verified Solution
Video duration:
4m
This video solution was recommended by our tutors as helpful for the problem above.
2173
views
Was this helpful?

Video transcript

welcome back everyone which of the following oxy assets is the strongest. So let's go ahead and look at twice A. So we have arsenic acid H three A. S. 04. And we can see that the ratio of oxygen to hydrogen is that we have four oxygen's 23 hydrogen atoms. And so we have one extra oxygen, two hydrogen, meaning that this is going to be a week oxy acid. And this is because we want to recall that for oxy acid strength. If we have two or more oxygen's that will correspond to a greater oxy acid strength And specifically two or more oxygen's two hydrogen. So now let's move on to our next given acid, which is H two S. C. 04 in choice B. Being celestic acid. Here, we can observe a ratio of four oxygen's 22 hydrogen. And so we have two extra oxygen's two hydrogen. And we're going to say that this is a strong oxy acid. But let's continue to choice C. To compare to see if we can rule it out. So so far we've only ruled out choice A. Moving on to choice C. We have phosphoric acid H three P 04. So we have a ratio of four oxygen's hydrogen is based on the formula and we can see that we have just one extra oxygen to hydrogen. So we would rule out Choice C. Moving on to choice D, which leaves us with sulfuric acid H two S. 04. We have a ratio of four oxygen's to two hydrogen. And so here we also have a ratio that is two extra oxygen's two are hydrogen atoms being are two hydrogen atoms here. So this is also a pretty strong oxy acid. So now we need to compare choices be where we have against Hellenic acid, H. Two S. E. 04 versus choice D. Which is our sulfuric acid H two S. 04. And so to compare these oxy assets, we want to next recall our trend for electro negativity where on our periodic table that is increasing towards the top. Right? And if we have a greater value for electro negativity, that's going to correspond to a greater oxy acid strength. So specifically that is in reference to the election negativity of our nonmetal. And so in this case we would be comparing our selenium to sulfur. So recall that on our periodic table. Selenium as well as sulfur are located in group six A. However, we see that sulfur lies across period three, whereas selenium lies across period four until sulfur is higher up on the periodic table and has a higher. Sorry, this says higher electro negativity, meaning that we would confirm therefore our sulfuric acid H two S. 04 is the strongest oxy acid, meaning that our final answer. After we rule out choice D. Or sorry, we rule out choice B. Her final answer is going to be choice D. As the strongest oxy acid. To complete this example. I hope that everything I explained was clear. If you have any questions, please leave them down below and I will see everyone in the next practice video.