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For this question, answer it on your work paper. In the box…

For this question, answer it on your work paper. In the box below, type “complete” when finished. Make sure to show all of your work. Below is an equation of A and B reacting together to create compound AB.   When this equation is at equilibrium, a flask contains a combination of A2 (Green), H2 (colorless) and HI (colorless).  The value of the equilibrium constant Kc for this reaction is 100 at a temperature of 200 kelvin.   A2(g) + B2(g)  ⇌ 2AB(g)   a)  If the green color of the mixture fades as the temperature is lowered, is the reaction forming AB exothermic or endothermic?   b) A flask is immersed in a constant-temperature bath maintained at 200 kelvin.  The flask initially contains the following:  [A2] = 0.124 M, [B2] = 0.036 M and [AB] = 0.25 M.  Will the concentration of AB increase or decrease as equilibrium is established?   c) What is the value of Kc for the following reaction conducted at 200 kelvin?   AB(g)  ⇌ ½ A2(g) + ½ B2(g)     d)  Assume the following system is at equilibrium:  A2(g) + B2(g)  ⇌ 2AB(g)    When this equilibrium is perturbed by a stress, the system will respond in order to establish a new position of equilibrium.  Predict the specified consequence of each stress by writing “increase”, “decrease” or “no change” after each sentence     Stress I)  When AB is removed from the vessel, the amount of A2 will  II)  When A2 is removed from the vessel, the amount of AB will III)  When the volume of the vessel is tripple, K will 

For this question, answer it on your work paper. In the box…

For this question, answer it on your work paper. In the box below, type “complete” when finished. Make sure to show all of your work.     Consider the following reaction:  NH4NO3(s) →  NH4+(aq) +NO3-(aq) a) Calculate the standard enthalpy change for this reaction at 25°                                                  b) Calculate the standard entropy change for this reaction at 25°                                                    c) Calculate the standard Gibbs free energy change for this reaction at 25°                                    d) What can be said about the spontaneity of this reaction at 25°C? (circle one)                               The reaction is not spontaneous at any temperature The reaction is spontaneous at all temperatures The reaction will only be spontaneous at low temperatures The reaction will only be spontaneous at high temperatures e)  Let’s just say, ΔHº = -241.8 kJ and ΔSº = -88.8 J K-1.  (Ignore ΔGº). Assuming that ΔHº = ΔH and ΔSº = ΔS at all temperatures, calculate the temperature criterion for spontaneity.  That is, indicate the minimum or maximum temperature required for spontaneity (e.g. T > ### or T