This, our slope, is the negative of the change in enthalpy about vaporization of the liquid over our gas constant R. Our X value is one over t or one over temperature of the liquid. And this is a constant that depends on the liquid being used. And if you graph this, you get exactly a linear line that has a negative slope shown by this negative sign here. So the magnitude of this value is this value here. And in fact, this is very useful because now if we're given some vapor pressure and we're given the temperature and we know the constant, we can easily find our slope. That is, we can find the change in enthalpy of vaporization.