Dichloromethane, CH2Cl2, is an organic solvent used for removing ...

Question

Dichloromethane, CH2Cl2, is an organic solvent used for removing caffeine from coffee beans. The following table gives the vapor pressure of dichloromethane at various tem- peratures. Fill in the rest of the table, and use the data to plot curves of Pvap versus T and ln Pvap versus 1/T.

Accepted Answer

hi everyone for this problem. It reads cesium iodide is commonly used as a simulator in experimental particle physics, the table below list the vapor pressure of solid cesium iodide at several temperatures. Use the Closius clap a run equation to calculate the entropy of sublimation of cesium iodide. So what we need to solve here is the and they'll be of sublimation. And we want to use the classiest clap Aaron equation. So we're going to use the linear form of the classiest clip Aaron equation and the linear form is Ln of P is equal to the negative entropy of sublimation over our times one over temperature plus C. And what this translates to when we write it out like this in linear form is y is equal to M. X plus B. Okay. And so plotting Ln of P versus one over temperature gives us a linear equation. And when we plot this, the linear equation we're going to get is why is equal to negative 23, x plus 17.5 - five. Okay. And so from this linear form of the equation M which is our slope, we see that M is going to equal the negative entropy of sublimation over our. So we can use this to solve for our entropy of sublimation, we can do that by setting both equal to each other. So M is going to equal the negative entropy of sublimation over our. And the question is asking us to solve for this value here. So we want to isolate this value. So we'll isolate this value by multiplying both sides of the equation by our Okay, so when we do that we get the negative entropy of sublimation is going to equal M times R. Okay now M is going to equal this value right here, negative 2 23,510 and r is the gas constant. R and r is equal to 8.314 jewels per mole, Calvin. And M. From our linear form of the equation is equal to negative 23,510. And this is in the unit of kelvin. So let's go ahead and plug these values in. So we get our entropy of sublimation is equal to M which is negative 23,510 kelvin times are 8.314 jewels over more times kelvin. Okay, so let's just take a look at our units, looking at our units, we see kelvin cancels and we'll be left with joules per mole, which is perfect. Okay, so let's simplify here. So we get the negative entropy of sublimation is going to equal, we're going to take negative 23,510 and multiply it by 8. ford and when we do that we get negative 1.95 Times 10 to the fifth jewels. So to make this positive we can go ahead and divide both sides by negative one so that we can get a positive value for entropy of sublimation. So this now becomes positive 1.95 times 10 to the five jewels. Okay, so what we did here was we divided both sides by -1. Alright, so now we have our final answer. And that is this here. So our entropy of sublimation is going to equal 1.95 times to the 5th jewels. And that is it for this problem. I hope this was helpful.

Dichloromethane, CH2Cl2, is an organic solvent used for removing caffeine from coffee beans. The following table gives the vapor pressure of dichloromethane at various tem- peratures. Fill in the rest of the table, and use the data to plot curves of Pvap versus T and ln Pvap versus 1/T.

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