14 aved ut of uestion In thermodynamics the Van der Waal s equation relates the mean pressure p of a substance to its molar volume v at some temperature T as follows p 7 v v1 4 RT Chemists are interested in the curves called isotherms described by this equation when the temperature is held fixed and R is a constant What is the value of dp dv when p 9 5 and v 8 6 O a 3433 377885 O b 1 316025 O c 1 358804 O d 0 945161 O e 1 322943