2. A gas occupies 320. ml at a pressure of 420.5 mmHg. Determine the volume if the pressure is decreased to 300. mmHg. a. 449 mL
C. 251 ml
b. 443 mL
d. 287 ml

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.