In the bromination reaction of trans-cinnamic acid, a student started with 300 mg oftrans-cinnamic acid and excess bromine. They then obtained 240 mg of pure2,3-dibromo-3-phenylpropanoic acid. What is the % yield of pure2,3-dibromo-3-phenylpropanoic acid?

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.