1. The problem statement, all variables and given/known data A spherical drop of a pure substance floats on top of the vapor of the same substance so the system vapor+drop is isolated. The drop has a surface tension σ. Show that at the thermodynamic equilibrium PL≠PV and calculate the difference. 2. Relevant equations Three laws of thermodynamics 3. The attempt at a solution I solved this one already but I would like to check my result. Following the three laws of thermodynamics and maximizing the entropy at the equilibrium yadda yadda yadda I got PL-PV=3σ/a, where a is the radius of the drop. The dimension of the result seems correct.