(a) Use the van’t Hoff equation in Problem 15.120 to derive the following expression, whic...

(a) Use the van’t Hoff equation in Problem 15.120 to derive the following expression, which relates the equilibrium constants at two different temperatures:

How does this equation support the prediction based on Le Châtelier’s principle about the shift in equilibrium with temperature? (b) The vapor pressures of water are 31.82 mmHg at 30°C and 92.51 mmHg at 50°C. Calculate the molar heat of vaporization of water.