What are the criteria for the spontaneity of chemical reactions

Define a is a tiny pavket of energy

Amixture initially contains a, b, and c in the following concentrations: [a] = 0.300 m , [b] = 1.05 m , and [c] = 0.550 m . the following reaction occurs and equilibrium is established: a+2b⇌c at equilibrium, [a] = 0.140 m and [c] = 0.710 m . calculate the value of the equilibrium constant, kc.

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.