 Okay, let's do a limiting reagent problem. So using the given reaction equation, if you heat 2.50 moles of iron and 3.00 moles of sulfur, how many moles of iron to sulfide are formed? Okay, so how do we do this? What we're going to figure out is, well, we've got to figure out the mole ratio of iron to iron to sulfide and sulfur to iron to sulfide. Okay? So we're going to convert both of these into iron sulfide and whichever one gives us the least amount, that's the amount of iron sulfide that we can make. Does everybody understand that? Okay, so let's do that. So what are we going to do? Here we're going to multiply it by 1. On the bottom here is what? 1 mole of iron. Everybody, help me out. 1 mole of iron. Is that right? 1 mole of iron? What about the top? 1 mole of iron to sulfide, right? Just like I just told you guys. Okay? You're on the bottom. So down here? Yeah. Somebody else help me out. What do I put up here? Okay, so what is this going to be? 3, 2, 8, 4, no, no. Moles of iron to sulfide. So which, how many moles of iron to sulfide are going to be formed? 2.50. 2.50. Why? Because what is the limiting reagent? What is? Iron is the limiting reagent. That's why. That's how you do those. So remember your gas to driving problems or sandwiches to how much you can work, okay? Any questions on this one? Nope. Okay.