1. The problem statement, all variables and given/known data For the van der Waals equation of state, confirm the following property: (∂P/∂T)V (∂T/∂V)P (∂V/∂P)T = -1 2. Relevant equations The van der Waals equation of state is: P = nRT/(v-nb) - an2/V2 *R, n, a, b are const. 3. The attempt at a solution I have come up with some partial derivatives, however, I cannot seem to figure out the algebra to make their product equal to -1. Perhaps my derivatives are incorrect? (∂P/∂T)V = nR/(v-nb)-1 (∂T/∂V)P = P - an2/V2 + 2abn3/V3 (∂V/∂P)T = 1/ (2an2/V3 - nRT/(v-nb)2) Any hints or ideas?