Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Consider the reversible reaction: A(g) 2B(g) At equilibrium, the concentration o

ID: 998653 • Letter: C

Question

Consider the reversible reaction: A(g) 2B(g) At equilibrium, the concentration of A is 0.381 M and that of B is 0.154 M. What is the value of the equilibrium constant, K_eq? 0.0622 0.404 1.06 2.47 16.1 Which one of the following, if changed, would change the value of the equilibrium constant, K_eq, of a reaction? Concentration of reactants concentration of the products temperature catalyst size of reaction vessel The reaction shown below is at equilibrium. Use Le Chatelier's principle to predict the effect of adding ammonia gas to the equilibrium reaction mixture N_2(g) + 3 H_2(g) 2NH_2 (g) The equilibrium post lion will remain unchanged The equilibrium position will shift to the right The equilibrium position will shift to the left. The equilibrium constant will increase. All of the nitrogen gas w ill be used up. A reaction will be spontaneous at all temperatures under which conditions? The reaction is endothermic and accompanied by an increase of disorder. The reaction is endothermic and accompanied by a decrease in disorder The reaction is exothermic and accompanied by an increase in disorder. The reaction is exothermic and accompanied by a decrease in disorder The reaction has a positive value for free energy change. Which of the following represents an exothermic reaction? Which of the following is a process with a negative Delta S? H_2O (l) rightarrow H_2 (g) CO_2(s) rightarrow CO_2(g) CaCO_3(s) rightarrow CaO(s) + CO_2 (g) dissolving sugar in water None of the choices are correct; Delta S cannot be negative.

Explanation / Answer

15)A(g)<à2B

Keq=[B]^2/[A]=(0.154M)^2/0.381M=0.0622

16)E)size of reaction vessel or volume

Keq=[product]^m/[reactant ]^n=[moles of product/V]^m/[moles of reactants/V]^n= (moles of product)^m/(moles of reactant)^n *(1/V)^m /(1/V)^n== (moles of product)^m/(moles of reactant)^n *(V)^n-m

k’eq=(moles of product)^m/(moles of reactant)^n *(V’)^n-m where V’ is changed volume

Keq is not equal to k’eq for n unequal to m.

17)C) the equilibrium will shift to the left (towards the reactant side ) to balance for increase in product concentration and re-establish its equilibrium

18)C)

When a reaction is exothermic it has –ve value of H and for increase of disorder S,entropy is positive.so G,gibbs free energy is negative ,hence the reaction is spontaneous

G=H-TS

19)B) heat is released as a by-product

20)A)

Liquid is changing its phase to less disordered or more compact form solid so its degree of disorderliness or entropy is decreasing