 So let's do this problem. It says at 46 degrees Celsius, a sample of ammonia gas exerts a pressure of 5.3 ATM. What is the pressure when the original volume of the gas is reduced to one-tenth of the original value at the same temperature? So I like this problem because it's a little more convoluted than the normal PV equals NRT type problem, okay, the ideal gas problem. In fact, it gives you a temperature value, which you're not going to use, that 46 degrees Celsius. It's not even within the workings of this problem. And in fact, I've written down here everything that we've needed to gather from all the information from the problem itself. So it's saying that the original pressure is 5.3 ATM and the original volume it doesn't give you. So we're just going to call it V1, okay? V2 it says is 10% of V1, so we'll just do that, okay? So well, you can see volume and pressure are changing. So what do we say we want to do? PV equals NRT and divide that by PV equals NRT. So changing for all the variables that are able to be changed. And we see here that only volume and pressure change. So cancel, cancel, cancel. So our new equation is P1 P1 equals P2 V2 and this is called Boyle's Law. So let's go ahead and rearrange this equation. We're looking for P2, okay? So let's solve for P2. Let's rearrange here in order to solve for P2. So I'm going to do that. So P2 is going to equal P1 V1 divided by V2 like that. Does that make sense algebraically how I did that? Okay, wonderful. So now it's just a plug and chuck problem. So what you'll notice is that we have V1 on top of V2 here, right? And we have V1 and V1 in both of these. So that's going to cancel out, is what's going to happen. So it's going to be 5.3 ATM times V1, which is just V1 divided by 0.10 V1. Like that, okay? So when we do this, cancel, cancel like that. So this is just going to be essentially multiplying that by 10. So it's going to be 5.3 ATM. It's going to be your new pressure. So that's how you do that. Are there any questions on that one? So what I'd like you guys to do is, of course, calculate these on your own just to make sure, of course, if you do it, get the right answer, right? Okay, cool. Just so you know how to use your calculator. Any questions on this one?