Question

Consider the following system at equilibrium where H° = 87.9 kJ/mol, and Kc = 1.20×10-2 , at 500 K. PCl5 (g) PCl3 (g) + Cl2 (g) When 0.32 moles of PCl5 (g) are added to the equilibrium system at constant temperature: the value of Kc A. increases. B. decreases. C. remains the same. the value of Qc A. is greater than Kc. B. is equal to Kc. C. is less than Kc. the reaction must: A. run in the forward direction to reestablish equilibrium. B. run in the reverse direction to reestablish equilibrium. C. remain the same. It is already at equilibrium. the concentration of PCl3 will: A. increase. B. decrease. C. remain the same.

Answer 1

delta H° = 87.9 kJ/mol, and Kc = 1.20×10-2 ,

at 500 K. PCl5 (g) --------------> PCl3 (g) + Cl2 (g)

When 0.32 moles of PCl5 (g) are added to the equilibrium system at constant temperature:

if 0.32 moles of PCl5 added , then the equilibrium shifts to forward direction.

the value of Kc : C). remains the same.

the value of Qc : C). is less than Kc.

the reaction must: A.) run in the forward direction to reestablish equilibrium.

the concentration of PCl3 will : A.) increase.