Which statement describes spontaneous processes?

proceed without continuous external influence and have an overall negative free energy change

proceed without continuous external influence and have an overall positive free energy change

proceed with continuous external influence and have an overall negative free energy change

proceed with continuous external influence and have an overall positive free energy change

Proceeding with a continuous external influence and having an overall negative free energy change.

Energy change in entropy is when a system changes to a more thermodynamic state. for example ice left in a room at room temperature, the ice will melt (change state) and go from solid to liquid.

Entropy is a measure of how much disorder a system has. When the molecules are spaced out - in a liquid it will have a greater entropy. There are also other factors that affect the entropy change of a system: addition in gas molecules or dissolving solutes ect.

whenever there is a positive entropy, there will be a negative free energy, this is because of the coefficient in the equation:

DeltaG = DeltaH - TDeltaS

- this is where Delta G is the Free energy change, Delta H is the enthalpy of the system change, T is the temperature of the system in kelvin and Delta S is the entropy change.

notice that there is the negative coefficient in the equation ... which explains the negative entropy on continuous external influences.

this equation can also be used to work out the feasibility of being able to carry out an experiment at varying temperatures, for example a reaction will only be feasible when there is a negative or = 0 free energy change. It can also be arranged to work out the minimum required temperature for an experiment to be feasible - simply by rearranging to make T the subject.