Calculate the vapor pressure of a solution containing 38.3 g of glycerin (C3H8O3) in 135 mL of water at 30.0 °C. The vapor pressure of pure water at this temperature is 31.8 torr. Assume that glycerin is not volatile and dissolves molecularly (i.e., it is not ionic), and use a density of 1.00 g>mL for the water.

Video transcript

Hello everyone. So this problem being asked, what is the vapor pressure of a solution might be dissolving? 27.3 g of fat to lean in water, 75 millions of water at 30 degrees Celsius. I'm assuming that now that the line is not volatile and it solves molecularly the vapor pressure of water at 30 degrees Celsius is equal to 31.82. Tour and the density of water is equal to 1. g per milliliters. So we're gonna go ahead and use this equation right over here. That's known as routes law. This is the pressure of the solution is equal to X of the solvent, multiplied by peeing of our sol vent. Alright, so let's go ahead and utilize this equation. So for this component over here, which will solve for first, that's equal to the moles of the solvent divided by the moles over salute plus the moles of our solvent. The most of solvent is equal to the moles of water, H 20. And that's equal to 175 mL. We go and multiply this by the density of the water. So for every 1.253 g, we have one millimeter. And then using the molar mass of water. So one mole for every 18.2 g. We see here that the middle layers cancel and the grams will cancel giving us that the moles of H 20. So the molds of the solvent is you go to 9. moles. Now for the moles of the solute. This is equal to 27.3 g of the now battling. Go ahead and then multiply this by the molar mass of it. So very one mole of this. We have 128.17 g. We'll see here that the units of g will counsel. Now the moles on my cell, you is going to be equal to 0. moles. All right again, the X solvent component is equal to We're using the calculated moles of the solvents. So we have 9. moles divided by 9.95713 moles plus the 0.212998 moles. Putting this into the calculator. We get that the X solvent Is equal to 0.9790 57. As for the p of the solution here is equal to 0.979057. multiplied by 31.82. Tour After putting this into the calculator, we get them the P solution is equal to 31.1536. Tour. Alright then. So for my final answer here, My final answer round to three significant figures is 31.2 units being tour. So this right here is going to be my final answer for the problem