Instructions: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Input: By the Third Law of Thermodynamics and a magnetic equivalent of this law, the critical magnetic field for a superconductor approaches a constant as temperature approaches absolute zero. This equation can be derived by showing that a Carnot engine run between two phases at two close temperatures has the same thermal efficiency. It can also be derived by finding the infinitesimal change in chemical potential for each of two phases in equilibrium with each other; that form of this equation says that the derivative of vapor pressure with respect to temperature equals the change in entropy over the change in volume. For 10 points, name this doubly-eponymous equation which gives the slope of the coexistence line in a pressure versus temperature plot.
Output:
Science