Avogadro's law states that our volume V and our moles n are directly proportional at constant pressure p and temperature t. It's named after Amedeo Avogadro and it shows that the volumes of gases are connected to their number of molecules. Here, we're going to say that the relationship between volume and moles is that V is directly proportional to moles, and again it happens when p and t are constant or fixed. The way we depict this with our movable pistons is if we take a look here at this image, we're going to say this container has a lot of dots, so it has a lot of moles or number of molecules. So moles would be high. To house all of these molecules we'd want our volume to be high, because gases like it when there's an optimal amount of distance between them. But what happens if I take some of these molecules of gases out? Well, our moles of gas would be low, and I no longer need as much space for them so my volume would be low. They both are high together or low together when pressure and temperature are constant or fixed. Now, how do we depict this in a plot? Since they're directly proportional, you'd say this line of V and n would show it increasing over time. Where you could start out at 0 liters and it increases over time as our moles increase.

Now, what would our adjusted formula or our Avogadro's Law formula be? That would just be V1n1 = V2n2. So our initial variables here, initial moles would be n1 initial volume V1. Final moles would be n2 final volume would be V2. So just remember our volume and moles are directly proportional, meaning they're both high together or low together when our pressure and temperature are constant or fixed.