1. The problem statement, all variables and given/known data It's not so much an exact question. One of the things I need to figure out to answer my question is if there is a formula of some sort that helps me calculate volume change through a phase change. The final volume of a liquid that vaporizes in to a gas, if the temperature and pressure is constant in an inclosed space. 2. Relevant equations 3. The attempt at a solution I was thinking maybe w=-nRTln (Vfinal)/(Vinitial) any help would be fantastic.