Hi there. Welcome to problem number 87. in problem number 87 we are given 62.7 g of cl two and we want to calculate the number of grams of carbon di sulfide CS two, The Question Mark, g of CS two. So this is a mass to mass problem. Specifically a masked mastoi geometry problem. Because we're starting with grams of Cl two And we're trying to find g of c. S. that's going to react with that. So, to do a strike geometry problem, we know that we're going to need a mole ratio. Well, we have a drawing here. The drawing shows us that for everyone CS two, it looks like we need three of those cl 2s. I was looking at the picture, we see three of those cl to us there. So it's a 1-3 ratio and we will need that here in a little bit. But let's go ahead and get started because what we need to do is convert from g to moles Of the CL two. Then we can convert two moles Of the CS two And then two g of CS two. Right? So those are three steps will be doing here. So let's go ahead and get started. First thing is to convert from 62.7 g of cl two. Jamal's of Cl two. And we're going to do that by using Molar Mass of Cl two. Since it's Cl two, we need to take two times the mass of chlorine, Which gives us 70.90 g. And there are that many g in one mole. And I put the g of cl two in the denominator. So that will cancel. So now we're at moles of cl two. We are ready to use that mole ratio. Remember from the drawing for every three Multiples in this case, M.nolds of Cl 2? We need to react one CS two. All right, so moles of seal to cancel. Now. Finally, we need to convert from moles of CS 2, 2 g. So we need the molar mass of CS two In every mole of CS two. There are 76.15 g. Notice to get from moles to grams were multiplying by this Mueller mass because that way the moles will cancel Right, calculating our answer and rounding it to three significant figures. Since 62.7 had three significant figures, I get 22 0.4 g of CS two is required to react completely With that 62.7 g of chlorine. Right? So 22.4 g of CS two. And that is our answer.