 Okay, so let's start today with doing one of these equilibrium constant problems. So this one is one of those where you just take the equilibrium constant and change it when you change the reaction around. So the question itself asks us, the equilibrium constant for the reaction of hydrogen plus iodine goes to 2 hydrogen iodide is 54.9 at 699.0 kelvin. What is the equilibrium constant for this new reaction for hydrogen iodide goes to 2 molecular hydrogen and 2 molecular iodine at the same conditions. Okay, so first thing we have to remember is when we change the coefficients or if we flip the reaction around, that's going to change this equilibrium constant for the reaction here. Okay, so hopefully you can see what we've done to this reaction, to make it this reaction, is first off we multiplied everything by 2. So each one of these coefficients has been multiplied by 2. Hopefully you can see that. See, we have one hydrogen here, two hydrogen here. Does everybody see that? Okay, and then 1 iodine, 2 iodines, 2 hydrogen iodine, 4 hydrogen iodine. Okay, so this thing has been multiplied by 2 and then what has happened is we flipped it over like that. So let's go ahead and attempt to figure out what the equilibrium constant would be one step at a time. I think that's the easiest way to do these things. So the first step is going to be, well, we're going to have to figure out what the equilibrium constant for the reaction, just multiplying everything by 2 is. Okay, so we're going to keep it the same way. We're not going to flip it yet, but we're going to multiply everything by 2. So let's figure out what the equilibrium constant for this reaction is. 2 molecular hydrogen plus 2 molecular iodine goes to 4 hydrogen iodine, like that. So hopefully you can see now this equation just flipped around, right? So we're going to call that K e q prime. So is it not confusing with this K e q here? So when we do that, when we multiply everything by 2, what we're going to do to the K e q is squared, okay? So we're going to raise it to the coefficient that we multiplied it by. So in other words, K e q prime is going to be K e q and in this case since we multiplied everything by 2, we're going to square it like that. Does that make sense? Yeah. Okay, so that's just the process. So in this case it's going to be 54.9 squared, like that. Okay, and you can solve for that if you want to, but I feel that it's easier to just take everything down to the final one and then punch it all into your calculator. That way you don't have all these decimal points to remember and stuff. Okay? So now, I guess is everybody okay with doing that first step? Okay? So we're going to multiply this by 3 and then we would raise that to 3. Okay? So let's do this next step now. So when we flip the reaction equation around, what do we do? In the case of K e q, we do the inverse of that K e q that was previous. Okay? So we're looking at this reaction now, right? Because all we've done from this reaction to this reaction is flip it over. Okay? So we want the K e q from this reaction to be flipped or to be inverted. Okay? So the inverse of that, so in other words, K e q double prime is going to be 1 over K e q prime, like that. Is everybody okay with that? So what is K e q prime? Well it's 54.9 squared, right? So let's write that in. So let's just solve for K e q double prime now. So we've got 1 over 54.9 squared, like that. And that's going to give you the answer without too much trouble. So I again would recommend that you do it like this. You can solve for this one here if you want to and then just to one divided by that to give you the same answer. Okay? But it's hard to write all this stuff down. So 54.9 squared of that. I do that, I get to what? 3 safe figs, 3.32 times 10 to the negative 4. And of course K e q doesn't have any units, so that's the new equilibrium constant. Okay? Are there any questions about that one? Okay, wonderful.