 Okay, let's try this one. So calculate the molarity of a solution made by diluting 50 mills, we'll put a decimal point after that 50, 50 mills of .10 molar HCl solution to a volume of 1 liter, okay? The one thing that we need is that those units have to cancel, right? So the units have to be the same. So are the volume units the same before and after? Are we seeing the same units? So we're gonna have to convert one to the other. Normally you want to keep them in like leaders because that's the common, you know, molarity unit, okay? So what was the formula that we're going to use, guys? M1v1 equals M2v2, good job, guys. Do we know any of those things? What do we know? So let's write, let's write all of these variables down really quick. M1v1, M2v2. So again, this is like, remember how we did the ideal gas law problems, how we were writing these things down? This is the exact same thing we're going to do here, okay? So do we know M1? Yeah. What is that? 0.1. Okay, so it says 0.10 molarity is the initial concentration of the solution, right? Do we know the initial volume, V1? 50 milliliters. Yes, it's 50 milliliters. And remember, we're gonna put that decimal point there just to keep safety. Do we know the molarity, the final molarity? No. So that's what we're looking for. And do we know the final volume? Yeah. Yeah, it's what? 1.0 liters. So what did we say? We're gonna have to convert that to another, right? The other thing we want to do, let's isolate the variable M2, okay? So how do we isolate that variable? We're gonna divide it both. Yeah, by V2. Very good, guys. So what's our new formula? It's M2 equals what? M1v1 divided by V2, right? Does that make sense to everyone? Okay, so now, well, let's convert this. The reason I wanted to show you this way is because this will cancel out those units of liters, okay, when we do the plug-and-show map, okay? So are all our units the same? What are the units of the concentration going to be in the end? Molarity, right? Okay, so let's make sure they don't. So what's M1? 0.10 molar. Molar is how we say that, okay? Molar, like you're back to. Do we know V1? Yes. What is that? 0.050 liters divided by V2, 1.0 liters. Does anything cancel out? Lators cancel. And does that give you a concentration unit? Yeah, so now just take your calculator, 0.1 times 0.05 divided by 1. So remember, how many sig figs is this gonna be, too? 2, right? So you can write it a number of ways, but I'm gonna write it in scientific notation. 5.0 times 10 to the negative 3 molar. Is there any questions about that one?