1. is this equation balanced? explain your answer. na + cl2 → nacl ?

No it is not balanced. The answer would be Na+Cl2=NaCl2 because it says l2

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.