Answer to Question #177088 in General Chemistry for Eisha

Question

I need help on these questions:

a. A 0.025 M sample of N2O4 (g) is allowed to come to equilibrium with NO2 (g) at 25C. Calculate the equilibrium concentrations of the following reaction. Keq = 0.045

b. The value of Keq at 30°C is 2.7 x 10-4. If 0.8 mol of NOCl is placed in a 2.0L container, calculate the concentrations at equilibrium. 

c. The equilibrium constant for the reaction is 2.4. Is the system at equilibrium? If not, what way will the reaction proceed?

d. Using the standard Gibbs free energy formula, at what temperature (Kelvin) would the reaction be at equilibrium? 

e. Decide whether a precipitate will form when 60 mL of 0.04 M CaCl2 (aq) are mixed with 40 mL of 0.01 M Na2SO4 (aq) at 25°C.

Answer 1

a) $=[NO_2]=3.6molL^{-1}$

b) $K_c=1.93$

c) No;the concentrations of the two reactants decrease significantly as the reaction proceeds. This tells you that at this temperature, the equilibrium lies to the right, i.e. the forward reaction is favored.

d) $3,032K$

e) A precipitate will form since the resulting compound is insoluble in water.