In this lesson you will learn how to select the property method used in System 7 Process Explorer. In order to select the property method of the simulation, you need to double click on thermal system or you can go from mode thermal system. To select the property method, click on tools, then property method, and then select your desired system: chemical, gas or oil. The chemical uses an NRTL equation, gas uses the Pang Robinson equation of state, the gas lee Kessler uses the lee Kessler method, oil uses the SRKKD equation of state and the API uses the API standard property method. The property slat for each can be viewed from the help file. If the user does not select any property then oil will be selected as the default. In order to go back to flow sheet simulation, you need to double click on flow sheet simulation or go to mode and select flow sheet design. This will conclude our lesson on selecting the property method used in System 7 Process Explorer.