Le Chatelier's Principle-Worksheet

Le Chatelier's Principle-Worksheet

Reversible Reactions   12:36

Name/Class/# :

Day, date :

1. Predict what will happen when the reaction volume is decreased in each of the following, after

balancing the reactions.

a) ___ CO2 (g) + ___ H2O (l)  ___ C6H12O6 (s) + ___ O2 (g)

b) ___ PCl5 (g)  ___ PCl3 (g) + ___ Cl2(g)

c) ___ H2 (g) + ___ CO2 (g)  ___H2O (g) + ___ CO (g)

2. Balance the exothermic reaction below:

___ NO2 (g) ___ N2O4 (g) ΔH = -58.0 kJ

Predict the effect of each of the following changes on this system at equilibrium (drive forward

reaction, drive reverse reaction, no effect).

a) add N2O4

b) increase the volume

c) Add NO2

d) remove NO2

e) decrease the temperature

3. Predict the shift in the following equilibrium system resulting from each of the following changes.

4HCI(g) + O2(g)  2H20(g) + 2Cl2(g) + 113kJ

(a) an increase in the temperature of the system

(b) a decrease in the system's total pressure due to an increase in the volume of the container

(c) an increase in the concentration of oxygen

(d) the addition of a catalyst

4. Predict which way the following equilibrium systems will shift when the total pressure is

increased.(NOTE: Some may have no shift)

a). N2(g) + O2(g)  2NO(g)

b). 2SO2(g) + O2(g)  2SO3(g)

c). 4NH3(g) + 5O2(g)  4NO(g) + 6H2O(g)

5. Which way will the following equilibrium shift if the total pressure on the system is decreased?

2C2H6(g) + 7O2(g) 4CO2(g) + 6H2O(g)

6. Consider the following reaction at equilibrium:

H2(g) + I2(g)  2HI(g)

a) Addition of more H2 gas to the container will do what to the rate of the forward reaction? Answer

________________________

b) If, for a while, the rate of the forward reaction is greater than the rate of the reverse reaction,

what will happen to the concentration of [HI]? Answer ________________________

QUIZ-REVERSIBLE REACTION (CHEMICAL EQUILIBRIA) _ IGCSE CHEMISTRY/O LEVEL CHEMISTRY

QUIZ-REVERSIBLE REACTION (CHEMICAL EQUILIBRIA) _ IGCSE CHEMISTRY/O LEVEL CHEMISTRY

quiz   19:16

1 In which of these equilibria is the forward reaction favoured by an increase in pressure? 

A 2HI(g) H2(g) + I2(g) 

B N2O4(g) 2NO2(g) 

C 2NO(g) + O2(g) 2NO2(g) 

D PCl 5(g) PCl 3(g) + Cl 2(g) 

2 Methanol is made in industry by a reaction between carbon monoxide and hydrogen. CO(g) + 2H2(g) CH3OH(g) ∆H = –90 kJ / mol The process is usually carried out at a temperature of 400°C. Which row correctly shows the effect on both the position of the equilibrium and on the rate of the reaction of increasing the temperature to above 400°C?

Chemical Equilibrium Exercise/Seatwork

Chemical Equilibrium Exercise/Seatwork

Worksheet   19:06

Chemical Equilibria - IGCSE Chemistry Exam Style Questions

Chemical Equilibria - IGCSE Chemistry Exam Style Questions

igcse exam   11:56

IGCSE Chemistry: Chemical Equilibrium MCQ

IGCSE Chemistry: Chemical Equilibrium MCQ

IGCSE Chemistry   11:19

IGCSE CHEMISTRY - CHEMICAL EQUILIBRIUM

NAME/CLASS/# :

DAY, DATE :

 

1. Consider the following reaction: 2SO2(g)  +  O2(g)  ⇄  2SO3(g)     ∆H =  -197  kJ/mol

            Which of the following will not shift the equilibrium to the right?

            A.        Adding more O2

            B.        Adding a catalyst

            C.        Increasing the pressure

            D.        Lowing the temperature

 

2. Consider the following equilibrium system: CaCO3(s)  ⇄ CaO(s) +  CO2(g)

          Which one of the following changes would cause the above system to shift left?

            A.        Add more CaO

            B.        Remove CaCO3

            C.        Decrease volume

            D.        Increase surface area of CaO

 

3. Consider the following equilibrium: SO2Cl2(g)  +  energy  ⇄  SO2(g)  +  Cl2(g)

            When the temperature is decreased, the equilibrium shifts

            A.        Left and [ SO2Cl2 ] increases

            B.        Left and [ SO2Cl2 ] decreases

            C.        Right and [ SO2Cl2 ] increases

            D.        Right and [ SO2Cl2 ] increases

 

4. Consider the following equilibrium: 2SO3(g)   ⇄  2SO2(g)  +  O2(g).       The volume of the system is decreased at a constant temperature. A new state of equilibrium is established by a  shift of the original equilibrium to the

            A. Left and [SO3] increases

            B. Right and [SO3] decreases

            C. Left and [SO3] remains unchanged

            D. Right and [SO3] remains unchanged

 

5. Consider the following equilibrium system: CO2(g)   +  H2(g)  ⇄  CO(g)  +  H2O(g) Which of the following, when added to the system above, would result in a net decrease in [H2O]?

            A. CO2

            B. H2

            C. CO

            D. H2

 

6. Consider the following equilibrium: C(s)  +  2H2(g)  ⇄ CH4(g)  +  74 kJ

            When a small amount of solid C is added to the system

            A. [H2] decreases

            B. [CH4] increases

            C. The temperature increases

            D. All concentrations remain constant

 

7. Consider the following equilibrium: 2NO(g)  +  Cl2(g)  ⇄  2NOCl(g)                     At constant temperature and volume, Cl2 is added to the above equilibrium   system. As equilibrium re-establishes, the

            A. [NOCl] will decrease

            B. The temperature increases

            C. [NO] will increase

            D. [NOCl] will increase

 

8. Consider the following equilibrium: Cl2O7(g)   +8H2(g)  ⇄  2HCl(g)  +  7H2O(g)

            Which of the following would increase the number of moles of HCl?

            A. Increase [H2O]

            B. Increase [Cl2O7]

            C. Increase total pressure

            D. Increase volume of the system

 

9. Consider the following equilibrium: 2HI(g)  ⇄           H2(g)    + I2(g)     ∆H = -68kJ

            Which of the following would cause the equilibrium to shift right?

            A. Increasing the volume

            B. Decreasing the volume

            C. Increasing the temperature

            D. Decreasing the temperature

 

10. A 1.00 L flask contains a gaseous equilibrium system. The addition of reactants to   this flask results in a

            A. Shift to the left and decrease in the concentration of products

            B. Shift to the left and increase in the concentration of products

            C. Shift to the right and decrease in the concentration of products

            D. Shift to the right and increase in the concentration of products

   

11.  When the temperature of an equilibrium system is increased, the equilibrium always shifts to favor the

            A. Exothermic reaction

            B. Endothermic reaction

            C. Formation of products

            D. Formation of reactants

 

12.  An equilibrium system shifts left when the

            A. Rate of the forward reaction is equal to the rate of the reverse reaction

            B. Rate of the forward reaction is less than the rate of the reverse reaction

            C. Rate of the forward reaction is greater than the rate of the reverse reaction

            A. Rate of the forward reaction and the rate of the reverse reaction are constant

 

13. Consider the following equilibrium: 2SO2(g)   +  O2(g)   ⇄   2SO3(g)   ∆H = -198 kJ

            There will be no shift in the equilibrium when

            A. More O2 is added

            B. Catalyst is added

            C. The volume is increased

            D. The temperature is increased

 

 

14. Consider the following equilibrium: 2NOCl(g)  ⇄  2NO(g)  +  Cl2(g)                    In a 1.0 L container at equilibrium there are 1.0 mol NOCl, 0.70 mol NO and 0.40 mol Cl2. At constant temperature and volume, 0.10 mol NOCl is added. The concentrations in the  “new” equilibrium in comparison to the concentrations in the “old” equilibrium are

 

	[NOCl]	[NO]	[Cl2]
A	new = old	new = old	new = old
B	new > old	new > old	new > old
C	new < old	new < old	new > old
D	new < old	new > old	new > old

 

 

15. Consider the following equilibrium: N2O4(g)  +  58 kJ  ⇄   2NO2(g)

            The equilibrium shifts right when

            A. NO2 is added

            B. N2O4 is removed

            C. The temperature is decreased

            D. The volume of the system is increased

 

16. Consider the following equilibrium: 2SO2(g)  +  O2(g) ⇄  2SO 3(g)

            Which of the following will shift the equilibrium to the right?

 

I. Adding more O2

II. Adding more SO3

III. Adding a catalyst

 

            A. I only

            B. III only

            C. I and II only

            D. II and III only

 

  

17. Consider the following equilibrium: 

                        energy   +  2NaClO3(s)  ⇌ 2NaCl(s)   +   3O2(g)

            Which of the following will cause a shift to the left?

            A.        adding more O2

            B.        adding more NaCl

            C.        removing some NaClO3

            D.        increasing the temperature

 

 

18. Consider the following equilibrium:

            CO(g)   +   2H2(g)   ⇌    CH3OH(g)   +   energy

            Which of the factors below would decrease the concentration of CH3OH at equilibrium?

            A.        an addition of CO

            B.        an increase in H2

            C.        a decrease in the temperature

            D.        an increase in the temperature

 

19. Consider the following equilibrium: 

                        energy   +  2NaClO3(s)  ⇌ 2NaCl(s)   +   3O2(g)

            Which of the following will cause a shift to the right?

            A.        adding more O2

            B.        adding more NaCl

            C.        removing some NaCl(s)

            D.        increasing the temperature

 

20. Consider the following equilibrium: 2SO2(g)  +  O2(g) ⇄  2SO 3(g)

            Which of the following will shift the equilibrium to the left?

 

I. Removing O2

II. Adding more SO3

III. Adding a catalyst

 

            A.        I only

            B.        III only

            C.        I and II only

            D.        II and III only

 

 

21. Consider the following equilibrium:   N2O4(g)    +   energy    ⇌    2NO2(g)

            How are N2O4 and NO2 affected by the addition of He into the container at   constant volume.

                        N2O4                  NO2

            A.        no change        no change

            B.        no change        increases

            C.        increases         decreases

            D.        decreases        increases

 

22. Which of the following stresses will cause a shift to the reactants?

            H2(g)   +    Br2(g)   ⇌   2HBr(g)   +   energy

            A.        increase [Br2]

            B.        increase [H2]

            C.        decrease temperature

            D.        increase temperature

 

23. Which of the following stresses will cause a shift to the products?

            H2(g)   +    Br2(g)   ⇌   2HBr(g)   +   energy

            A.        decrease [Br2]

            B.        decrease [H2]

            C.        decrease temperature

            D.        increase temperature

 

24. Which of the following two stresses will each cause the system to shift to the left?    

            2SO2(g)  +  O2(g) ⇄  2SO 3(g)   +  energy

           

            A.        decrease temperature and decrease [O2]

            B.        increase temperature and increase [SO3]

            C.        increase temperature and decrease [SO3]

            D.        decrease temperature and increase [SO2]

 

25. SrCO3(s)   +  215 kJ   ⇌    SrO(s)     +  CO2(g)

               Which of the    following conditions would produce the greatest yield of SrO(s)?

                        Temperature                Pressure

            A.        low                              low

            B.        low                              high

            C.        high                             low

            D.        high                             high

 

26. The Haber Process is used to produce ammonia commercially according to the following equilibrium:

            N2(g)  +  3H2(g)  ⇌   2NH3(g)    +   energy

            Which of the following conditions will produce the highest yield of ammonia?

            A.        increase temperature and increase pressure

            B.        increase temperature and decrease pressure

            C.        decrease temperature and increase pressure

            D.        decrease temperature and decrease pressure

 

27. Consider the following reaction: 2SO2(g)  +  O2(g)  ⇄  2SO3(g)     ∆H =  -197  kJ/mol

            If the volume is increased what happens to position of the equilibrium?

            A.        shifts to the right

            B.        shifts to the left

            C.        no shift

            D.        shifts in the exothermic direction

 

28. Consider the following reaction: 2NH3(g) + energy  ⇄ N2(g)  +  3H2(g)     

            If the volume is increased what happens to position of the equilibrium?

            A.        shifts to the right

            B.        shifts to the left

            C.        no shift

            D.        shifts in the exothermic direction

 

29. Consider the following reaction: SrCO3(s)   +  215 kJ   ⇌    SrO(s)     +  CO2(g)  

            If the volume is decreased what happens to position of the equilibrium?

            A.        shifts to the right

            B.        shifts to the left

            C.        no shift

            D.        shifts in the exothermic direction

 

30. Consider the following reaction: H2(g)   +    Br2(g)   ⇌   2HBr(g)   +   energy

            If the volume is increased what happens to position of the equilibrium?

            A.        shifts to the right

            B.        shifts to the left

            C.        no shift

            D.        shifts in the exothermic direction

 

  

31. Consider the following reaction: N2O4(g)    +   energy    ⇌    2NO2(g)

            If the volume is decreased what happens to position of the equilibrium?

            A.        shifts to the right

            B.        shifts to the left

            C.        no shift

            D.        shifts in the exothermic direction

 

32. Given the equilibrium reaction in a closed system: 

H2(g) + I2(g) + heat <--> 2 HI(g). 

What will be the result of an increase in temperature?

1. The equilibrium will shift to the left and [H2] will increase

2. The equilibrium will shift to the right and [HI] will increase

3. The equilibrium will shift to the left and [H2] will decrease

4. The equilibrium will shift to the right and [HI] will decrease

33.  In the reaction, CO (g) + NO2 (g)  CO2 (g) + NO (g), which of the following changes would result in the formation of more products at equilibrium?

1.  increasing the pressure

2.  removing CO (g) from the reaction

3. adding NO2 (g) to the reaction

4. adding CO2 to the reaction.