The following data present the temperatures at which certain vapor pressures are achieved for dichloromethane (CH2Cl2) and methyl iodide (CH3I): (c) The order of volatility of these two substances changes as the temperature is increased. What quantity must be different for the two substances for this phenom- enon to occur?

Video transcript

Hi everyone sir. Ask consider the compounds metal acetate and acetone and as the temperature increases, their order of volatility also changes for this to occur, we need to determine the quantity that must be different from method acetone and acetone. For this. We're gonna look at the classes clapper an equation. This is L. N. Of the second vapor pressure by by the first favorite pressure equal to negative the entropy of vaporization abide by the r gas constant. That was one over the second temperature in kelvin -1 over the first temperature in Kelvin. And we can also write this as Ln eagle two negative dot H. The ap What about art Times one over T pussy. And this is why equals M. X plus B. In linear form. And since the order of the volatility changes with temperature, the plots for acetone and methyl acetate is going to cross at the same temperature at some point have a slope. The entropy of vaporization in the white intercept must be different. Thanks for watching my video and I hope it was helpful