What bond angles do you expect for each of the following? (d) The O¬B¬O angle in BO33-

Video transcript

Hey everyone, we're asked what is the expected bond angle for the oxygen arsenic? Oxygen bond in RC. Right first, let's go ahead and determine the total number of electrons will have in our lewis structure. Starting with our arsenic, we know that this is in our group five A. So this will have five valence electrons since we have only one of arsenic will multiply it by one to get a total of five. Now looking at our oxygen, we know that this is in our group six A. So this will have six valence electrons since we have three of oxygen. We're going to multiply this by three to get a total of 18 electrons. And since we have that -3 charge, this means that we will have to add plus three electrons. So in total we will need to draw out 26 electrons. Now let's go ahead and draw this out. Starting with arsenic, we know that this is our central atom since it is the least electro negative atom and we're going to connect our three oxygen's. And to complete those 26 electrons, we end up with three lone pairs on each oxygen And each oxygen will also have a formal charge of -1. As we can see right here, we have three electron groups surrounding our arsenic which is three atoms and zero lone pairs. So this means that we have a tribunal planer geometry And our bond angle is going to be 120° for our oxygen arsenic, oxygen bond and this is going to be our final answer. Now, I hope that made sense and let us know if you have any questions.