Question: is cocl2 hcl endothermic or exothermic?
Answer: The Co(H2O)62+ complex is pink, and the CoCl42- complex is blue. This reaction is endothermic as written, so adding heat causes the equilibrium constant to shift to the right. This, correspondingly, makes the solution blue. When the AgNO3 is added, Cl- is removed from solution.