CHEMICAL EQUILIBRIUM

(Zuli Aswiwik, 2006. Modules Chemical Equilibrium. UM: Malang)

1. Below are the traits of a dynamic equilibrium reactions, namely:
a. Concentrations of reactants and reaction products at
b. The reaction takes place in one direction
c. Number of moles of reactants and reaction products at 
d. Forward reaction rate equal to the rate of the reaction to the left 
e. Concentrations of reactants and reaction products is constantly changing 

2. Factors that may affect the equilibrium shifts are: 
a. Catalytic 
b. Surface area 
c. Nature of the substance 
d. Type of reaction 
e. Changes in concentration 

3. Note the following equilibrium reactionFe3 + (aq) + SCN-(aq) = FeSCN2 + (aq)If the crystal FeCl3 was added to the reaction then 
a. The reaction will shift to the left 
b. The reaction will shift to the right 
c. No reaction equilibrium
d. The reaction will stop 
e. The reaction does not shift 

4. Note the equilibrium reaction below!N2 (g) + 3H2 (g) = 2NH3 (g)The reaction will shift to the right if: 
a. Pressure is raised
b. Dilution 
c. Volume enlarged 
d. N2 concentration reduced
e. Pressure is lowered 

5. The statement below is true, excepta. Catalysts will affect how quickly equilibrium is reachedb. Catalysts may affect the equilibrium shiftsc. The catalyst can increase the rate of reaction.d. The catalyst does not affect the equilibrium shifts
 e. Catalysts can reduce the activation energy.

6. What is the price of the equilibrium constant (Kc) for the following reaction3C2H2 (g) = C6H6 (g)If it is known at the equilibrium state are 0.5 M 0.5 M C2H2 and C6H6
a. 0.0625 
b. 0.25
c. 0.4
d. 2.5 
e. 4 

7. At T 10 ° C in room L contained 0.2 mol PCl5 equilibrium, 0.3 mol PCl3, and 0.1 mol Cl2 according to the following reactionPCl5 (g) = PCl3 (g) + Cl2 (g)Determine the equilibrium constant prices?
a. 0,015 
b. 0.15
c. 1.5
d. 6.67
e. 66.7

8. At a temperature of 27oC in the room with a certain volume of pressurized gas contained 1 atm N2O4 which decomposes to NO2 gas. The equation
 N2O4 (g) = 2NO2 (g). When the equilibrium is reached in the room turns out there is a 20% NO2. Calculate Kp at this temperature? 
a. 0.05 
b. 0.5 
c. 5
d. 20
e. 50B. Problem Description
1. Write the equilibrium constant (Kc) for the reaction below! 
a. 2CaSO4 (s) = 2CaO (s) + 2SO2 (g) + 2O2 (g) 
b. 2CO2 (g) = 2CO (g) + O2 (g) 
c. 2ZnS (s) + 3O2 (g) = 2ZnO (s) + 2SO2 (g)
d. 2NO2 (g) + 7H2 (g) = 2NH3 (g) + 4H2O (g) 

2. Reaction H2 (g) + S2 (s) = 2H2S (g) takes place at a temperature of 700 ° C. at equilibrium 2.5 mol H2 is reacted with 1.35 x 10-5 mol 8.70 mol S2 produce H2S with room volume 12.0 L. Calculate the price of Kc for the reaction! 

3. What is the price of Kp for the reaction at a temperature of 1273oC2CO (g) + O2 (g) = 2CO2 (g) if Kc 2.24 x 1022 at the same temperature? 

4. Note the following reaction:N2 (g) + O2 (g) = 2NO (g)What is the price of Kp at a temperature of 2200oC if the partial pressure of N2, O2, NO is 0.15 atm; 0.33 atm, and 0.5 atm? 

5. Note the following equilibrium systemSO2 (g) + Cl2 (g) = SO2Cl2 (g)Predict which way the equilibrium will shift if, 
a. Cl2 added 
b. SO2Cl2 taken from the system
c. SO2 is taken from the system 

6. Note the following equilibrium process!PCl5 (g) = PCl3 (g) + Cl 2 (g) ΔH = +92.5 kJ What happens if: 
a. Volume increased 
b. Pressure is raised 
c. The temperature is raised
d. Adding chlorine to the mix
e. The catalyst is added to the system 

7. Note the following reaction?I2 (g) + Cl2 (g) = 2ICl (g)A total of 0.5 moles of I2 reacted with 0.5 mol Cl2 in a 1 L beakers at a specific temperature. Once equilibrium is reached concentrations formed ICL was 0.4 mol.
a. Write the equilibrium constant (Kc) 
b. Determine the concentration of I2 and Cl2 at equilibrium 
c. Determine the value of the equilibrium constant (Kc)