 So, let's attempt to take this equation and derive an equation where we can find the density using the ideal gas variables, okay, the density of a particular gas, okay. So, this is the ideal gas law, Pb equals nRt, right, and we also know the density formula. What is that? Density equals mass divided by volume, like that. So, since we have that, right, we should be able to inter-convert this to solve for volume, okay, so let's do that. So, multiply both sides by b, right, so we're going to get Bd equals m, right, and then divide both sides by d, right, so let's do that. We're going to have B equals m divided by d. Is everybody okay with that? Okay, so now what we can do is we can take B and plug in for B in the ideal gas equation. Okay, so let's do that, P times m divided by d equals nRt, like that, okay, with that. Okay, so let's rearrange this equation because we want to solve for density, right. So, multiply both sides by d, that's going to cancel that, right, we're going to get Pm equals nRtd, okay, so now what are we going to do? Let's divide both sides by nRt, right, nRt because we want to get d by itself. Is everybody okay with that? Cancel, cancel, cancel, cancel, cancel, cancel, like that. Pm over nRt equals d. Is everybody okay with me doing that? So, one other thing we know, another conversion we know is the molar mass. So the molar mass, remember, is what? The grams per mole, right, so what is the variable that we use for grams usually, right, do we have m in here? Yes, yes. Yeah, so m, and for moles what do we use? M. M, do we have an m in there? Yes. Yeah, so let's circle that. So we have something like this, m and m, right, so that's the same thing as that, so we can replace that portion with the molar mass, okay. So in other words, the derived equation is density equals pressure of the gas, so this is the density of the gas equals the pressure of the gas times the molar mass of the gas divided by the ideal gas constant times temperature, okay. So that's the derived ideal gas equation for density, and that's how to do it. Any questions on doing this thing before we kill this video?