Why is fresh water considered a limited resource?
A. It cannot be renewed.
B. It is found underground.
C. It can be easily polluted.
D. It is not evenly distributed.

Spontaneity tell us the direction of the reaction, but not how fast it goes. gibbs free energy brings together enthalpy, entropy and temperature in one easy formula. g = h - ts. and, finally the sign of delta g is always negative for a spontaneous reaction.

They are all full and don't need any more electrons in there outer shell.