When I solve an exercise to calculate Gibbs Free Energs delta G I look in Tables and collect for Data for enthalpy and entropy and fill them in the formula deltaG = deltaH - T*deltaS. I am confused about the system and surrounding. Is this treated a open or closed System? Is it isothern .. I think yes. How this manifested in my calculation below?
Welcome to the forum.
There is no clear distinction between system and surroundings in these types of problems, because the reactants gains energy from environment itself by increasing the entropy of the environment (environment is nothing but our Earth which is considered a closed system). It all depends how we define the boundary of the system.
The - ve value obtained after using Gibbs free energy equation indicates that the process will happen spontaneously. (with large increase increase in entropy).
When we talk about Gibbs free energy, it must be constant temperature and constant pressure process. The environment and reactants are all considered to be in thermal equilibrium at all times. So, temperature (T) of the environment does not change at all.
Note: I am from engineering background so my depth of knowledge in Chemistry is little bit less.