Clausius-Clapeyron Equation Example 1

Jules Bruno
Was this helpful?
the vapor pressure of a substance is measured over range of temperatures. A plot of the natural log of the vapor pressure versus the inverse of the temperatures in Calvin produces a straight line with a slope of negative 2.79 times 10 to the three kelvin find the entropy of vaporization of the substance. All right. So we need to find entropy of vaporization which is just our delta H of Vape. Now remember from the classes clapper on equation in its linear form, it's negative delta H. V over R equals your slope M. Here. What do we have? Well, we know the slope is negative 2.79 times 10 to the three Kelvin. We don't know what our entropy of vaporization is. That's what we're looking to find. Our is our gas constant 8.314 jewels over moles times K. Multiply here both sides by negative jewels over moles, times K. And when I do that, my kelvin's cancel out and my units will be in jewels promote negative times A negative will give me a positive at the end. So we have here delta H of vaporization here. This is 36 fix or answer. Also need three sig figs. This comes out to 2.32 Times 10 to before Jules promote. So this would represent my entropy of vaporization for this particular question