Ch.14 - Chemical EquilibriumWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Most chemical reactions never go to completion where all the reactants are converted into products. Instead these reactions reach a chemical equilibrium

Chemistry & Equilibrium

Concept #1: Understanding Chemical Equilibrium. 

A reaction reaches equilibrium once the rate of the forward reaction equals the rate of the reverse reaction. Once at equilibrium there is no net change in the concentration of reactants or products. 

Whereas the rate constant, k, is affected by factors dealing with the rate of reaction, the equilibrium constant, K, is affected by only temperature. 

Practice: Which one of the following statements does not describe the equilibrium state?

a. While at equilibrium, a dynamic process is still occurring.  

b. The concentration of the reactants is equal to the concentration of the products.

c. The concentration of the reactants and products reach a constant level.

d. At equilibrium, the net concentration of all species is not changing.

e. All are true. 

The Equilibrium Constant K

Associated with any reaction at equilibrium is the equilibrium constant K. Its numerical value determines if reactants or products are more greatly favored within a reaction. 

Concept #2: Understanding the Equilibrium Constant. 

The equilibrium constant K is a ratio of products to reactants. It only deals with gaseous or aqueous compounds. 

Example #1: Write the equilibrium expression for the following reaction:

 

Practice: State which is greater in amount: reactants or products, based on the given equilibrium constant, K. 

Practice: The decomposition of nitrogen monoxide can be achieved under high temperatures to create the products of nitrogen and oxygen gas. 

6 NO(aq) ⇌ 3 N2(aq) + 3 O2(aq) 

a) What is the equilibrium equation for the reaction above?

b) What is the equilibrium expression for the reverse reaction. 

Practice: The equilibrium constant, K, for 2 NO (g) + O2 (g) ⇌ 2 NO2 (g) is 6.9 x 102

What is the [NO] in an equilibrium mixture of gaseous NO, O2, and NO2 at 500 K that contains 1.5 x 10 –2 M O2 and 4.3 x 10 –3 M NO2?

Kp and Kc

When dealing with equilibrium units in terms of pressure the equilibrium constant of Kp must be used, but if the equilibrium units are in molarity then we must use the equilibrium constant of Kc

Concept #3: The Different Types of Equilibrium Constants. 

Kp and Kc are related to one another by the following equation below: 

Example #2: For the reaction above, the Kc = 4.9 x 10-9 at 25oC. Which of the following statements is true?

  1. The reaction is favored in the forward direction.
  2. The concentration of the products is greater than the concentration of the reactants.
  3. The reaction is favored in the reverse direction.
  4. The value of Kp will be larger than the value of Kc

Practice: Methane (CH4) reacts with hydrogen sulfide to yield hydrogen gas and carbon disulfide, a solvent used in the manufacturing rayon and cellophane. What is the value of Kc at 1000 K if the partial pressures in an equilibrium mixture at 1000 K are 0.20 atm methane, 0.15 atm hydrogen sulfide, 0.30 atm carbon disulfide and 0.10 atm hydrogen gas? 

CH4 (g) + 2 H2S (g) ⇌ 4 H2 (g) + CS2 (g)

Determination of the value for Δn can help us determine if Kp is greater than, less than or equal to Kc

Practice: In which of the given reactants is Kp greater than, less than and equal to Kc?

a) SO3 (g) + NO (g) ⇌ SO2 (g) + NO2 (g)

b) P4 (s) + 5 O4 (g) ⇌ P4O10 (s)

c) 4 NH3 (g) + 3 O2 (g) ⇌ 2 N2 (g) + 6 H2O (g)

Practice: Given the hypothetical reaction 2 A (s) + ? B (g) ⇌ 3 C (g), Kp = 0.0105 and Kc = 0.45 at 250 degrees Celsius. What is the value of the coefficient of B? 

Hess’s Law and the Equilibrium Constant K

The old concept of Hess’s Law can be applied to our new concept of the Equilibrium Constant K. 

Example #3: The equilibrium constant K for the first reaction is 6.83 x 10-12 at 1000 K. Calculate K for the second reaction. 

Reversing a reaction gives us the reciprocal of K, while multiplying a reaction by a value makes it the power for K. 

Example #4: Calculate the rate constant, Kc, for the reaction below:

H (g) + Br (g) ----> HBr (g)

Use the following information to calculate Kc.

      H2 (g) ---> 2 H (g)                                         Kc = 11.8

      Br2 (g) ---> 2 Br (g)                                      Kc = 1.15 x 10-5

      H2 (g) + Br2 (g) --->  2 HBr (g)                   Kc = 2.78 x 103

Example #5: Hess's Law & Equilibrium Constant K

Example #6: Hess's Law & Equilibrium Constant K

Additional Problems
When a reaction reaches equilibrium, 1. the rate of the reverse reaction is zero. 2. the rate of the forward reaction and the rate of the reverse reaction are equal to zero. 3. all reaction stops. 4. the rate of the forward reaction is zero. 5. the forward and reverse reaction rates are equal
Which of the following statements(s) is/are true with respect of the following reaction at constant temperature.  A2(g) + 3B2(g) ↔ AB2(g) +AB4(g)             K = 5.04 x 10  -5 at 25.0°C i. At equilibrium the rate of the reverse reaction is faster than the rate of the forward reaction. ii. Changing the concentration of reactants and products will NOT affect the value of K. ​iii. At equilibrium, the concentration of products is greater than the concentration of reactants. A. i only B. ii only C. iii only D. i and ii E. ii and iii 
Give the direction of the reaction, if K << 1 A) The forward reaction is favored. B) The reverse reaction is favored. C) Neither direction is favored. D) If the temperature is raised, then the forward reaction is favored. E) If the temperature is raised, then the reverse reaction is favored.
Consider the following reaction: Al(OH)3 (s) ↔ Al 3+ (aq) + 3 OH- (aq)        Kc = 1.3 x 10 -33 Which statement is correct? a. there will be a high concentration of products b. the concentration of Al 3+ will be the same as the concentration of OH - c. the reaction will go to completion d. the concentration of the products will be very small e. increasing the concentration of Al(OH) 3 will shift the reaction to the right  
Which of the following statements is/are true regarding equilibrium in general? i. at equilibrium, the forward and reverse reactions stop. ii. at equilibrium, the rate of the forward reaction is greater than the rate of the reverse reaction iii. at equilibrium, the concentration of reactants and products are constant. A. i only  B. ii only C. iii only D. i and ii E. i and iii
Choose the statement which is most accurate based on the data in the figure. A) The reaction favors the reactants. B) The reaction favors the products. C) At equilibrium, the concentrations of the reactants and the products are equal. D) The reaction is 0th-order. E) The reaction rate is independent of concentration.
Kc has a value of 100.0 at 25.0 oC for the reaction of 2X + 2Y ⟺ 3Z. What is the value of Kp for this reaction? a) 4.1 b) 22 c) 100.0 d) 220.0 e) none of the given answers
Which of the following statement(s) is/are true with respect to the following reaction at constant temperature?  A2 (g)  +   3 B2 (g)   ⇌   AB 2 (g)  +  AB4 (g)                  K = 2.32 x 10  5 at 25.0 oC i) At equilibrium the rate of the forward reaction is faster than the rate of the reverse reaction.  ii) Changing the concentrations of reactants and products will change the value of the equilibrium constant.  iii) At equilibrium the concentration of products is greater than the concentration of reactants.    a) i only b) ii only  c) iii only  d) i and ii  e) ii and iii
Give the direction of the reaction, if K ≈ 1. A) The forward reaction is favored. B) The reverse reaction is favored. C) Neither direction is favored. D) If the temperature is raised, then the forward reaction is favored. E) If the temperature is raised, then the reverse reaction is favored.
The reaction 2 H2O (l) ⇌ H3O+ (aq) + OH− (aq) has a Kc of 1.0 x10−14 at 25oC. What is the Kc of the reaction at the same temperature? 2 H3O+ (aq) + 2 OH− (aq) ⇌ 4 H 2O (l) A. 1.0x1028 B. 2.0x1014 C. 2.0x10−14 D. 1.0x10−28
The following equilibria are known at 823 K: Zn (s) + H2O (g) ⇌ ZnO (s) + H2 (g) Kc = 0.015   Zn (s) + CO2 (g) ⇌ ZnO (s) + CO (g) Kc = 0.0020   Based on the above equilibria, calculate the Kc of the following reaction: CO (g) + H2O (g) ⇌ H2 (g) + CO2 (g) Kc = ? A. 7.5 B. 0.13 C. 3.0x10−5 D. 0.013
In which of the following reactions will K c = Kp ? A) S(s) + O2 (g) ⇌ SO2(g) B) 2H2(l) ⇌ 2H2(g) + O2(g) C) H2CO3 (s) ⇌ H2O(l) + CO2(g) D) N2(g) + 3Cl2 (g) ⇌ 2NCl3(g) E) CH4(g) + H2O(g) ⇌ CO(g) + 3H2(g)
The following reactions occur at 500 K. Arrange them in order of increasing tendency to proceed to completion (least → greatest tendency) 1. 2NOCl ⇌ 2NO + Cl2      Kp = 1.7 x 10 -2 2. 2SO3 ⇌ 2SO2 + O2      Kp = 1.3 x 10 -5 3. 2NO2 ⇌ 2NO + O2        Kp = 5.9 x 10 -5 A. 2 <3 <1      B. 1 <2 <3     C. 3 <1 <2        D. 3 <2 <1        E. 2 <1 <3
Which is a proper description of chemical equilibrium? a) The frequencies of reactant and of product collisions are identical. b) The concentrations of products and reactants are identical. c) The velocities of product and reactant molecules are identical. d) Reactant molecules react to form products, while product molecules are reacting to form reactants.
If the following reaction is carried out in a sealed container:               2 SO 3(g) ⇌  2 SO 2(g) + O 2(g)  a state of equilibrium can be reached if the container initially contains: A) SO3 only.         B) SO2 and O2 only.           C) SO3 and O2 only. D) SO3, SO2, and O2. E) any of these combinations of reactants and products.    
The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant. 2 SO2(g) + O2(g) ⇌ 2 SO3(g) Kc = 1.7 × 10 6 SO3(g) ⇌ 1/2 O2(g) + SO2(g) Kc = ? A) 3.4 × 10 2 B) 8.5 C) 1.3 × 10 3 D) 1.2 × 10 -6 E) 7.7 × 10 -4
Consider the following reactions at 25°C: Reaction                                                           Kc 2 NO (g) ⇌ N2 (g) + O2 (g)                           1 × 10   30 2 H2O (g) ⇌ 2 H2 (g) + O2 (g)                       5 × 10   −82 2 CO (g) + O2 (g) ⇌ 2 CO2 (g)                      3 × 10   91 Which compound is most likely to dissociate and give O2 (g) at 25°C? 1. CO2 2. NO 3. CO 4. H2O
Chemical equilibrium is the result of a) formation of products equal in mass to the mass of the reactants. b) the unavailability of one of reactants. c) a stoppage of further reaction. d) opposing reactions attaining equal speeds.
At 25°C, Kc = 2.34 × 10−6 for the reaction NH4(NH2CO2) (s) → 2 NH3 (g) + CO2 (g) . Calculate Kp at 25°C for this reaction. 1. 3.43 × 10−2 2. 14.4 3. 2.02 × 10−5 4. 3.56 × 104 5. 1.40 × 10−3
Consider the reactions SO2(g) → O2(g) + S(s)                          K   c = 2.5 × 10−53 SO3(g) → 1/2 O2(g) + SO2(g)                K c = 4.0 × 10−13 Calculate Kc for the reaction 2 S(s) + 3O2(g) → 2 SO3(g). 1. 1.6 × 10103 2. 1.0 × 1065 3. 1.6 × 1080 4. 1.0 × 10130 5. 1.6 × 1040
Calculate Kp for the reaction below at 400°C if Kc at 400°C for this reaction is 2.1 x 10 -2. 2 NOCl(g) ⇌ 2NO(g) + Cl2(g) A. 3.8 x 10-4 B. 1.2 C. 0.70 D. 1.7 x 10-3 E. 2.1 x 10-2  
Which of the following statements is correct for a reaction that has  K << 1?     A)    The forward reaction is faster than the reverse reaction.     B)    The reverse reaction is faster than the forward reaction.     C)    The equilibrium favors the products.     D)    The equilibrium favors the reactants.     E)    None of these statements is correct.
Chemical equilibrium is the result of: a decrease in  speed of a reaction the unavailability of one of the reactants a stoppage of further reaction opposing reactions attaining equal speeds formation of products equal in mass to the reactants 
The equilibrium constant for the reaction Ni (s) + 4CO (g) ⇌ Ni(CO) 4 (g) is 1.2 × 10–4 at 25°C. What is the equilibrium constant for the reaction Ni(CO)4 (g) ⇌ Ni (s) + 4CO (g)?
Nitrogen gas can spontaneously combine with hydrogen gas to create hydrazine based on the following reaction:                                                  N     2 (g)  +  2 H2 (g) ⇌ N2H4 (g)                                     What is the Kc for the forward reaction if the equilibrium concentrations of N 2, H2 and N2H4 are 0.800 atm, 0.500 atm and 0.010 atm respectively at 25oC ? 
Given the hypothetical reaction ? A (g) + 2 B (g) ⇌ 3 C (g), Kp = 1.287 x 10-7 and Kc = 0.63 at 300oC. What is the value of the coefficient of A?    
Given the reaction: A (aq) + 2 B (aq) ⇌ C (aq) + 3 D (aq)                            K = 7.4 * 10 -3 Solve for the K for this reaction: 3 A (aq) + 6 B (aq) ⇌3 C (aq) + 9 D (aq)                       K = Solve for the K for: C (aq) + 3 D (aq)⇌ A (aq) + 2 B (aq)                             K =    
Which is the proper description of chemical equilibrium?   A. The frequencies of reactant and product collisions are identical B. The concentrations of products and reactants are identical C. The velocities of product and reactant molecules are identical D. Reactant molecules react to form products as fast as product molecules are reacting to from reactants.
Chemical equilibrium is the result of:   A. a decrease in speed of a reaction B. the unavailability of one of the reactants C. a stoppage of further reaction D. opposing reactions attaining equal speeds E. formation of products equal in mass to the reactants
The value of an equilibrium constant can be used to predict each of these except the A. Direction of a reaction B. Extent of a reaction C. Quantity of a reactants remaining at equilibrium D. Time remaining to reach equilibrium
Which of the following represents a heterogeneous equilibrium? N2O4 (g) ⇌  2 NO2 (g) CH3COOH (aq)  +  H2O (l)  ⇌ CH3COO­­­­- (aq)  +  H3O+ (aq) CaCO3 (s) ⇌ CaO (s) +  CO2 (g) NH3 (aq)  +  H2O (l)  ⇌ NH4+ (aq) +  OH­­­­- (aq) None of the above.   
For the following reaction, 2 A (g) + 3 B (g) ⇌ 2 C(g), Kp = 4.9 x 106 at 25oC. Which of the following statements is true? The reaction is favored in the forward direction. The concentration of the products is less than the concentration of the reactants. The reaction is favored in the reverse direction. The value of Kp will be larger than the value of Kc.   
In which of the given reactions is K p greater than, less than and equal to K c? a. WO3 (s) + 3 H2 (g) ⇌  W (s)  +  3 H2O (g) (Choose from the choices below)   b. 2 Ag (s)  +  Br2 (g) ⇌ 2 AgBr (s)   c. 2 FeCl3 (s)  + 3 H2O (g) ⇌  Fe2O3 (s) + 6 HCl (g)   
Consider the two gaseaous equilibria SO2(g) + 1/2 O2(g) ⇌ SO3(g)  K1 2SO3(g) ⇌ 2SO2(g) + O2(g)  K2 The values of the equilibrium constants K1 and K2 are related by A. K22 = K1 B. K2 = (K1)2 C. K2 = 1/K12 D. K2 = 1/K2 E. none of the above   
When reaction 1 and 2 below are added together, the result is reaction 3.       1)  H 2O (l) + HNO 2 (aq) ⇌ H 3O+ (aq) + NO 2‒ (aq)              K 1 = 4.50 × 10 ‒4       2)  H 3O + (aq) + OH ‒ (aq) ⇌ 2 H 2O (l)                                   K 2 = 1.00 × 10 14       3)  HNO 2 (aq) + OH ‒ (aq) ⇌ NO 2‒ (aq) + H 2O (l)                K 3=? Find the equilibrium constant, K 3.              A) 4.50 × 10‒18              B) 2.22 × 1017              C) 4.50 × 1010                 D) 1.00 × 1014
At 500°C the equilibrium constant, Kp, is 4.00 x 10-4 for the equilibrium: 2HCN(g)  ⇋ H2(g) + C2N2(g) What is Kc for the following reaction? H2(g) + C2N2(g)  ⇋ 2HCN(g) A)  2.00 x 10-4                        B) -4.00 x 10-4            C) 1.25 x 103 D) 2.50 x 103                           E) 4.00 x 104
Determine the Kc for the following 2 CO (g) + O2 (g) ⇌ 2 CO2 (g)        Kp = 3.34 x 10 -3   at 2727 °C a. 83.3 b. 1.47 x 10 -7 c. 0.823 d. 1.36 x 10 -5 e. 0.748  
Give the direction of the reaction, if K >> 1. A) The forward reaction is favored. B) The reverse reaction is favored. C) Neither direction is favored. D) If the temperature is raised, then the forward reaction is favored. E) If the temperature is raised, then the reverse reaction is favored.
The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant. H2 (g) + Br2 (g) ⇌ 2 HBr (g)                        K  c = 3.8 x 104 4 HBr (g) ⇌ 2 H2 (g) + 2 Br2 (g)                  K c = ? A) 1.9 x 104 B) 5.1 x 10-3 C) 2.6 x 10-5 D) 6.9 x 10-10 E) 1.6 x 103
What is the Δn for the following equation in relating K c to Kp? C3H8 (g) + 5 O2 (g) ⇌ 3 CO2 (g) + 4 H2O (l) A) 3 B) -1 C) -3 D) 2 E) 1
Use the following equilibria. SnO2 (s) + 2 CO (g) <==> Sn (s) + 2CO2(g)   Kc = 1.4 x1010 CO (g) + H2O (g) <==> CO2 (g) + H2 (g)   Kc = 9.0 x 1012 to calculate the Kc of this reaction SnO2 (s) + 2 H2 (g) <==> Sn (s) + 2 H2O (g)  Kc= ? A. 1.40 x 1010 B. 1.50 x 10-3 C. 1.13 x 1036 D. 1.73 x 10-16 E. 7.78 x 10-4
What is dynamic equilibrium?
What is the significance of the equilibrium constant? What does a large equilibrium constant tell us about a reaction? A small one?
What happens to the value of the equilibrium constant for a reaction if the reaction equation is reversed? Multiplied by a constant?
Why are the concentrations of solids and liquids omitted from equilibrium expressions?
Does the value of the equilibrium constant depend on the initial concentrations of the reactants and products?
Do the equilibrium concentrations of the reactants and products depend on their initial concentrations?
What happens to a chemical system at equilibrium when that equilibrium is disturbed?
Explain the difference between Kc and Kp.
For a given reaction, how are Kc and Kp related?
What units should be used when expressing concentrations or partial pressures in the equilibrium constant? What are the units of Kp and Kc? Explain.
If two reactions sum to an overall reaction, and the equilibrium constants for the two reactions are K1 and K2, what is the equilibrium constant for the overall reaction?
The equilibrium constant, Kc, for the reaction. 2A(g) + 3B(g) → 3C(g) is 2.85 x 10  3 at 48°C. What is the value of Kp at this temperature?A. 1.98 x 106B. 184C. 4.10D. 4.43 x 104E. 198 x 106
In which of the following equations will the value of Kp be less than, greater than or equal to the value of Kc at 37°C?a. C (s) + O2 (g) ↔ CO2 (g)b. 2 BrNO (g) ↔ 2 NO (g) + Br 2 (g)c. Br2 (g) + Cl2 (g) ↔ 2 BrCl (g)d. 2 H2 (g) + S2 (g) ↔ 2 H2S (g)e. CH4 (g) + H2O (g) ↔ CO (g) + 3 H 2 (g)
True or False? When a reaction achieves equilibrium, the rate of the forward reaction goes to zero so the concentrations stop changing.A) TrueB) False
The equilibrium constant for the reaction2 SO2(g) + O2(g) ⇌ 2 SO3(g)has the value K = 4 x 1024 at 298 K. Find the value of K for the reaction.SO2(g) + 1/2O2(g) ⇌ SO3(g)at the same temperature.1. 1.58 x 1052. 1.73 x 1023. 8.23 x 1084. 2 x 10125. 3.95 x 10106. 2.64 x 106  
The equilibrium constant for the overall reaction:Ag+(aq) + 2NH3(aq) ⇌ Ag(NH3)2+(aq)is known to be Kc = 1.105x107. This reaction occurs in two steps corresponding to the addition of the first and then the second ammonia molecules. You have been able to measure the equilibrium constant for the first step:Ag+(aq) + NH3(aq) ⇌ Ag(NH3)+(aq)     Kc = 1.7x103 What is the equilibrium constant for the second step?a) 9.7x10−7b) 2.3x105c) 1.88x1010d) 1.54x10−3e) 6.5x103
For the reaction,cis-C4H8(g) ⇌ trans-C4H8(g)the equilibrium constant, Kc, at 200° C is 112. Which of the following statements is correct after equilibrium has been established? a) The concentration of the reactant is larger than the concentration of the product.b) The concentrations depend on whether a catalyst is present.c) The concentration of the product is larger than the concentration of the reactant.d) The concentrations depend on whether the reaction starts with pure cis or pure trans.e) At equilibrium, the concentrations of the reactants and products are equal.
An equilibrium constant with a small magnitude indicates that a system favors _____ when it reaches equilibrium.a) reactantsb) productsc) neither reactants nor productsd) both reactants and productse) none of the above
The equilibrium constant is given for one of the reactions below. Determine the value of the missing equilibrium constant.H2(g) + Br2(g) ⇌ 2HBr(g)          K c = 3.8 x 1042HBr(g) ⇌ H2(g) + Br2(g)           Kc = ?A) 1.9 x 10 4B) 5.3 x 20 –4C) 2.6 x 10 –5D) 6.4 x 10 –4E) 1.6 x 10 3
Of each of these equations, determine the change in the number of moles (change in n gas) (a) (NH4)2CO3(s) →2NH3(g) + CO2(g) + H2O(g) ___________ mol (b) H2(g) + Cl2(g) → 2HCl (g) ___________ mol (c) 2H2(g) + O2(g) → 2H2O (l) ___________ mol (d) 2Na(s) + Cl2(g) → 2NaCl (s) ___________ mol
The value of Kc for the reaction A ⇌ B is 1.4x10−20. At equilibriuma) The amount of A is much larger than the amount of B.b) The amount of A equals the amount of B.c) The amount of A is slightly less than the amount of B.d) The amount of A is very close to the amount of B.e) The amount of A is much less than the amount of B.
The equilibrium constant, Kc = 9.63 for the reacion shown below.2 A + B → 3 CWhat is the correct value of K for the reaction shown below?6 C → 4 A + 2 Ba. 0.0519b. 92.7c. 0.0108d. 0.104e. 0.208 
Which of the following statement(s) is/are true with respect to the following reaction at constant temperatureA2 (g) + 3B2 (g) ⇌ AB2 (g) + AB 4 (g)              K = 1.98 x 10  4 at 25.0°Ci. At equilibrium the rate of the reverse reaction is equal to the rate of the forward reaction.ii. Changing the concentration of reactants and products will change the value of K.iii. At equilibrium the concentration of reactants is greater than the concentration of products. A. i onlyB. ii onlyC. iii onlyD. i and iiE. ii and iii
Select all the true statements regarding chemical equilibrium: A. The concentrations of reactants and products remain constant. B. The concentrations of reactants and products are equal. C. Reactants are still being converted to products (and vice versa). D. The rates of the forward and reverse reactions are equal.
What is the equilibrium constant for the reactionNH3(aq) + H3O+ (aq) ⇌ NH4+ (aq) + H2O(l)Given the following informationNH3(aq) + H2O(l) ⇌ NH4+(aq) + OH–(aq)     Kc = 1.8x10 –54H2O(l) ⇌ 2OH –(aq) + 2H3O+(aq)               Kc = 1x10 –28a) 1.8x10 9b) 4.5x10 7c) 9.0x10 10d) 1.8x10 –5e) 2.7x10 6
The correct units for the equilibrium constant Kp for the reactionN2 + 3 H2 ⇌ 2 NH3  are1. atm −12. None; Kp is dimensionless. 3. atm4. atm25. atm −2 
For the reaction:N2(g)+3H2(g) ⇌ 2NH3(g)Kp = 2.75×10−3 at 265 °C .What is Kc for the reaction at this temperature? Enter your answer numerically.
Select all the true statements regarding chemical equilibrium. At equilibrium... i) the concentrations of reactants and products are equal. ii) the concentrations of reactant and products remain constant. iii) reactants are still being converted to products (and vice versa). iv) the rates of the forward and reverse reactions are equal.
Determine the value of the equilibrium constant, Kgoal, for the reaction:C(s) +1/2 O2(g) + H2(g) ⇌ 1/2 CH3OH(g) + 1/ 2CO(g), Kgoal=? by making use of the following information:1. CO2(g)+3H2(g) ⇌ CH3OH(g)+H2O(g), K1 = 1.40×1022. CO(g)+H2O(g) ⇌ CO2(g)+H2(g), K2 = 1.00×1053. 2C(s)+O2(g) ⇌ 2CO(g), K3 = 2.10×1047Express your answer numerically.    
Given that2 X(g)  + 3 Cl2(g)  ⟺  2 XCl3   K1= 5XCl3(g) + Cl2(g) ⟺ XCl5(g)     K2 = 4What is K3 for the reaction below?2 X(g) + 5 Cl2(g)  ⟺  2 XCl5(g)    K3a) 80b) 60c) 5/4d) 4/5e) 20
Given the following information,HF(aq) ⇌ H+ (aq) + F - (aq)                      K  c = 6.8 X 10-4H2C2O4 (aq) ⇌ 2H+ (aq) + C 2O4-2 (aq)      K c = 3.8 X 10-6determine the value of Kc for the reaction2HF(aq) + C2O4-2 (aq) ⇌ 2F - (aq) + H2C2O4 (aq)A) 0.12B) 1.2x10-3 C) 1.20D) 3.50E) 2.3 x 10-4
If Kp = 0.0520 at 60oC, calculate Kc at this temperature for the reaction:NH4SH (s) ⇄ NH3 (g) + H2S (g)A. 1.42B. 19.2C. 38.8D. 6.96x10−5
What is Δn for the following equation in relating Kc to Kp?N2O4(g) ⇌ 2NO2(g)A) 3B) -1C) -2D) 2E) 1
For the reversible reactionA(g) ⇌ B(g)which k values would indicate that there is more B than A at equilibrium? 
For each of these equations, determine the change in the number of moles (change in n gas).i) (NH4)2CO3 (s) → 2NH3 (g) +CO2 (g) + H2O (g)ii) H2 (g) +Cl2 (g) → 2HCl (g)iii) 2H2 (g) + O2 (g) → 2H2O (l)iv) 2Na (s) +Cl2 (g) → 2NaCl (s)
The value of an equilibrium constant can be used to predict each of these except  thea) direction of a reaction.b) extent of a reaction.c) quantity of reactant(s) remaining  at a equilibrium.d) time required to reach equilibrium. 
The value of the equilibrium constant at a given temperature for the reaction is 0.200.                2 HI(g) ⇌ H 2(g) + I 2(g)        Find the value of the equilibrium constant for the reaction:                H 2(g) + I 2(g) ⇌ 2 HI(g)        A)  0.200        B)  0.0400            C)  5.00             D)  0.500        E)  -0.200 
Which equilibrium constant represents a reaction that is most product favored?    A) Keq = 0.025      B) Keq = 5.2        C) Keq = 8.4 × 10−5        D) Keq = 6.3 × 105 
The equilibrium constant Kc = 6.35 for the reaction shown below. The enthalpy change for this reaction at 25°C is -25.6 kJ.2 A + B → 3CWhat is the correct value of K for the reaction shown below?3/2 C → A + 1/2 BA. 0.397B. 0.079C. 2.52D. 0.157E. 3.18
Which of the statements is FALSE regarding the equilibrium constant, K c?a) If Kc is greater than one the equilibrium is said to lie towards products.b) Kc for the B ⇌ A reaction is the inverse of the K c for the A ⇌ B reaction.c) The value of Kc depends on the physical states of the reactants.d) Kc is constant regardless of the temperature of the reaction.e) Kc is a unitless constant.
Determine the equilibrium constant, Kgoal, for the reaction4PCl5(g) → P4(s)+10Cl2(g),           Kgoal=?by making use of the following information: P4(s)+6Cl2(g) → 4PCl3(g),         K1=2.00x1019 PCl5(g) → PCl3(g)+Cl2(g),         K2=1.13x10-2
At 300 K, Kp = 0.143 for the reaction N2O4(g ) ⇌ 2NO2(g).a. What is Kp at 300 K for the reaction 2NO2(g) ⇌ N2O4(g)?b. What is Kp at 300 K for the reaction 2N 2O4(g) ⇌ 4NO2(g)?c. What is Kp at 300 K for the reaction NO2(g) ⇌ 1/2N2O4(g)?
A reaction with an equilibrium constant K c = 1.5 x 10 25 would consist of which of the following at equilibrium:A. essentially all reactantsB. some reactants and products with reactants slightly favoredC. some reactants and products with products slightly favoredD. approximately equal reactants and productsE. essentially all products
A + 2B → 2C      Kc = 2.392C → D               Kc = 0.176Calculate the value of the equilibrium constant for the reactionD → A + 2B         Kc = ?
The K of the reaction: NO2(g) + NO3(g) ⇌ N2O5(g) is K= 2.1x10-20. What can be said about this reaction?a. At equilibrium the concentration of products and reactants is about the sameb. At equilibrium the concentration of products is much greater than the concentration of reactantsc. At equilibrium the concentration of reactants is much greater than that of productsd. There are no reactants left over once the reaction reaches equilibrium
The acid dissociation constant Ka for HSO4- is 1.26 x 10-2 and Kb for NH3 is 1.8 x 10-5.HSO4- (aq) + NH3 (aq)--> SO42- (aq) + NH4+(aq)Which direction will the reaction be favored and will the Kc for this reaction be, >1 or <1? Explain your reasoning.
The reaction below has an equilibrium constant Kp = 2.2 x 10 6  at 298 K.2COF2(g)⇌CO2(g)+CF4(g)Calculate Kp for the reaction below.COF2(g) ⇌ 1/2CO2(g) + 1/2CF4(g)Express your answer using two significant figures.
The equilibrium-constant of the reactionNO2(g) + NO3(g) ⇌ N2O5(g)is K = 2.1 × 10−20. What can be said about this reaction?a. At equilibrium the concentration of products and reactants is about the same.b. At equilibrium the concentration of products is much greater than the concentration of reactants.c. At equilibrium the concentration of reactants is much greater than that of products.d. There are no reactants left over once the reaction reaches equilibrium.
For the following chemical reactions:Original: 2 H2S (g)⇌ 2 H2 (g) + S2 (g)                   K  P = 2.4 X 10  −4 New : 2 H2 (g) + S2 (g) ⇌ 2 H2S (g)                       K  P’ = ????Solve for KP’ of the new chemical reaction and select the best description below. KP’                          Original Reaction                  New Reaction a. 4.2 X 103            Favors products                    Favors reactantsb. 4.2 X 103            Favors reactants                   Favors productsc. −2.4 X 10−4        Favors reactants                   Favors reactantsd. −2.4 X 10−4        Favors products                    Favors products  e. 2.4 X 10−4          Favors reactants                    Favors reactants
Calculate the value of Kp for the equation. C (s) + CO2 (g) ⇌ 2 CO (g) given that at a certain temperature C (s) + 2 H2O (g) ⇌ CO2 (g) + 2 H2 (g) ; Kp1= 3.09   H2 (g) + CO2 (g) ⇌ H2O (g) + CO (g)   ; Kp2=0.619
For the reversible reactionA(g) ⇌ B(g)which K values would indicate that there is more B than A at equilibrium?i. K = 9 x 10-9ii. K = 0.2iii. K = 9000iv. K = 9 x 109
The reaction below has an equilibrium constant of Kp = 2.26 x 104 at 298 K.CO(g) + 2H2(g) ⇌ CH3OH(g)What is the value of K p for the reaction below? AND Will the reaction products or reactants be favored at Equilibrium?1/2CH3OH(g) ⇌ 1/2CO(g) + H2(g)A) Kp = -2.26 x 104 ;  Products are favoredB) Kp = 4.4 x 10 –4 ;    Reactants are favoredC) Kp = 6.7 x 10 –3 ;    Products are favoredD) Kp = 6.7 x 10 –3 ;     Reactants are favoredE) Kp = 1.5 x 10 2 ;      Products are favored
Calculate the value of the equilibrium constant for the reaction: D in equilibrium with A+2B.A+2B in equilibrium with 2C Kc= 2.352C in equilibrium with D Kc= 0.182
The following pictures represent mixtures of A 2B 4 molecules and AB 2 molecules, which interconvert according to the equation:  A 2B 4 ⇌ 2 AB 2.If mixture (1) is at equilibrium, which of the other mixtures are also at equilibrium?A) mixture (2)B) mixture (3)C) mixture (4)D) None of the other mixtures are at equilibrium
Phosgene, COCl2, a poisonous gas, decomposes according to the equationCOCl2(g) ⇋ CO(g) + Cl2(g)Calculate Kp for this reaction if Kc = 0.083 at 900ºC.A)  0.125B)  8.0            C)  6.1            D)  0.16          E)  0.083
For A + 2B → 2C  Kc= 2.79                     For 2C → D  Kc= 0.106 Calculate the value of the equilibrium constant for the reaction: D → A + 2B Kc=?
Calculate the value of the equilibrium constant K for the hypothetical reaction 2D → A + 2B from the following information: A + 2B → C   Kc = 3.3 C → 2D       Kc = 0.041    
The following equilibrium constants have been determined for oxalic acid at 25 °C.H2C2O4 (aq) ⟺ H+ (aq) + HC2O4 - (aq)    K1 = 6.5 x 10 -2HC2O4- (aq) ⟺ H+ (aq) + C2O4 2- (aq)        K 2 = 6.1 x 10 -5Calculate the equilibrium constant for the following reaction at the same temperature:                     C  2O4 2− + 2H + ⟺ H2C2O4 (aq)  
Consider the simple one-step reaction: A(g) ⇌ B(g)Since the reaction occurs in a single step, the forward reaction has a rate of kfor[A] and the reverse reaction has a rate of krev[B].How does this explain the reason behind Le Chateliers principle?
What does it mean to describe a reaction as “reversible”?
When writing an equation, how is a reversible reaction distinguished from a nonreversible reaction?
If a reaction is reversible, when can it be said to have reached equilibrium?
Is a system at equilibrium if the rate constants of the forward and reverse reactions are equal?
If the concentrations of products and reactants are equal, is the system at equilibrium?
If you observe the following reaction at equilibrium, is it possible to tell whether the reaction started with pure NO2 or with pure N2O4?2NO2(g) ⇌ N2 O4(g)
The following reaction occurs when a burner on a gas stove is lit:CH4(g) + 2O2(g) ⇌ CO2(g) + 2H2 O(g)Is an equilibrium among CH4, O2, CO2, and H2O established under these conditions? Explain your answer.
For the reaction A → B, the ratio of products to reactants at equilibrium is always the same number, no matter how much A or B is initially present. Interestingly, in contrast, the ratio of products to reactants for the reaction C → 2D does depend on how much of C and D you have initially.Explain this observation. Which ratio is independent of the starting amounts of C and D?
H2 and I2 are combined in a flask and allowed to react according to the following reaction: H2(g) + I2(g) ⇌ 2 HI(g)Examine the figures (sequential in time) and answer the following questions.Which figure represents the point at which equilibrium is reached?
A chemist trying to synthesize a particular compound attempts two different synthesis reactions. The equilibrium constants for the two reactions are 23.3 and 2.2 x 104 at room temperature. However, upon carrying out both reactions for 15 minutes, the chemist finds that the reaction with the smaller equilibrium constant produced more of the desired product.Explain how this might be possible.
At a given temperature, the elementary reaction A ⇌ B in the forward direction is first order in A with a rate constant of 2.50 x 102 s-1. The reverse reaction is first order in B and the rate constant is 7.50 x 10-2 s-1.a. What is the value of the equilibrium constant for the reaction  A ⇌ B at this temperature?b. What is the value of the equilibrium constant for the reaction  B ⇌ A at this temperature?  
The reaction below has an equilibrium constant Kp=2.2×106 at 298 K.    2COF2(g) ⇌ CO2(g) + CF4(g) a. Calculate Kp for the reaction 4COF2(g) ⇌ 2CO2(g) + 2CF4(g). Express your answer using two significant figures. b. Predict whether reactants or products will be favored at equilibrium in the equation above. c. Calculate Kp for the reaction below. Express your answer using two significant figures.      2/3 COF2(g) ⇌ 1/3 CO2(g) + 1/3 CF4(g)  d. Predict whether reactants or products will be favored at equilibrium in the equation above. e. Calculate Kp for the reaction below. Express your answer using two significant figures.      2CO2(g) + 2CF4(g) ⇌ 4COF2(g)  f. Predict whether reactants or products will be favored at equilibrium in the equation above.
Convert the values of K c to values of KP or the values of KP to values of K c.(a) N2(g) + 3H2(g) ⇌ 2NH3(g)            K c = 0.50 at 400 °C
You may want to reference (Page 685) Section 15.4 while completing this problem.The reaction shown here has a Kp = 5.1 × 102 at 850 K: CH4(g) + CO2(g) ⇌ 2CO(g) + 2H2(g)Find Kc for the reaction at this temperature.
Convert the values of K c to values of KP or the values of KP to values of K c.(b) H2(g) + I2(g) ⇌ 2HI(g)       K c = 50.2 at 448 °C
Convert the values of K c to values of KP or the values of KP to values of K c.(c) Na2 SO4 ·10H2 O(s) ⇌ Na 2 SO4(s) + 10H2 O(g)    KP = 4.08 × 10−25 at 25 °C
Convert the values of K c to values of KP or the values of KP to values of K c.(d) H2 O(l) ⇌ H2 O(g)          KP = 0.122 at 50 °C
Convert the values of Kc to values of KP or the values of KP to values of Kc.(a) Cl2(g) + Br2(g) ⇌ 2BrCl(g)              K c = 4.7 × 10−2 at 25 °C
Convert the values of Kc to values of KP or the values of KP to values of Kc.(b) 2SO2(g) + O2(g) ⇌ 2SO3(g)       KP = 48.2 at 500 °C
Calculate Kc for each reaction: I2 (g) ⇌ 2I(g); Kp = 6.26 x 10–22 (at 298 K)
Convert the values of Kc to values of KP or the values of KP to values of Kc.(c) CaCl2 ·6H2 O(s) ⇌ CaCl2(s) + 6H2 O(g)      KP = 5.09 × 10−44 at 25 °C
Calculate Kc for each reaction: CH4(g) + H2O(g) ⇌ CO(g) + 3H2(g); Kp = 7.7 x 1024 (at 298 K)
Calculate Kc for each reaction: I2(g) + Cl2(g) ⇌ 2ICl(g); Kp = 81.9 (at 298 K)
Convert the values of Kc to values of KP or the values of KP to values of Kc.(d) H2 O(l) ⇌ H2 O(g)     KP = 0.196 at 60 °C
You may want to reference (Pages 685 - 685) Section 15.4 while completing this problem.Calculate Kp for each of the following reactions: N2O4(g) ⇌ 2NO2(g); Kc = 5.9 x 10 – 3 (at 298 K)
You may want to reference (Pages 685 - 685) Section 15.4 while completing this problem.Calculate Kp for each of the following reactions: N2(g) + 3H2(g) ⇌ 2NH3(g); Kc = 3.7 x 108 (at 298 K)
You may want to reference (Pages 685 - 685) Section 15.4 while completing this problem.Calculate Kp for each of the following reactions: N2(g) + O2(g) ⇌ 2NO(g); Kc = 4.10 x 10–31 (at 298 K)
You may want to reference (Pages 685 - 685) Section 15.4 while completing this problem.Consider the following reaction and corresponding value of Kc: H2(g) + I2(g) ⇌ 2HI(g); Kc = 6.2 x 102  at 25 oCWhat is the value of Kp K_{ m p}at this temperature?
You may want to reference (Pages 685 - 693) Section 15.7 while completing this problem.Nitrogen dioxide dimerizes according to the following reaction: 2 NO2(g) ⇌ N2O4(g); Kp = 6.7298A 2.35-L container contains 0.056 mol of NO2 and 0.085 mol of N2O4 298. Calculate Kc for the reaction.
Calculate Kp for each of the following reactions. Express your answer using two significant figures. a. N2O4(g) ⇌ 2NO2(g)                     K  c = 5.9 × 10−3 (at 298 K) b. N2(g) + 3H2(g) ⇌ 2NH3(g)            K c = 3.7 × 108 (at 298 K) c. N2(g) + O2(g) ⇌ 2NO (g)               K  c = 4.10 × 10−31 (at 298 K)
The equilibrium constant, Kp, for the following reaction is 0.110 at 298 K.NH4HS(s) → NH3(g) + H2S(g)Calculate Kc for this reaction at this temperature.
The reaction below has an equilibrium constant of Kp=2.2*106 at 298 K. 2COF2(g)+CO2(g)+CF4(g) Calculate Kp for the following reactions below.  a. COF2(g) + 1/2CO2(g)+1/2CF4(g) b. 6COF2(g) + 3CO2(g)+3CF4(g) c. CO2(g)+CF4(g)+2COF2(g)  
Calculate the value of Kp for the equation. C(s) + CO2(g) ⇌ 2CO(g)                              Kp=? given that at a certain temperature C(s) + 2H2O(g) ⇌ CO2(g) + 2H2(g)              Kp1 = 3.09 H2(g) + CO2(g) ⇌ H2O(g) + CO(g)               Kp2 =0.619
Under which circumstances are Kp and Kc equal for the reaction aA(g) + bB(g) ⇌ cC(g) + dD(g)?
Benzene is one of the compounds used as octane enhancers in unleaded gasoline. It is manufactured by the catalytic conversion of acetylene to benzene: 3C2 H2(g) ⟶ C6 H6(g). Which value of Kc would make this reaction most useful commercially? Kc ≈ 0.01, Kc ≈ 1, or Kc ≈ 10. Explain your answer.
A particular reaction has an equilibrium constant of Kp = 0.50. A reaction mixture is prepared in which all the reactants and products are in their standard states. In which direction will the reaction proceed?
For a titration to be effective, the reaction must be rapid and the yield of the reaction must essentially be 100%. Is Kc > 1, < 1, or ≈ 1 for a titration reaction?
For a precipitation reaction to be useful in a gravimetric analysis, the product of the reaction must be insoluble. Is Kc > 1, < 1, or ≈ 1 for a useful precipitation reaction?
When the following reaction comes to equilibrium, will the concentrations of the reactants or products be greater?A(g) + B(g) ⇌ 2 C(g); Kc = 1.4 x 10–5
The reaction below has an equilibrium constant of Kp = 2.26 x 104 at 298 K.CO(g) + 2 H2(g) ⇌ CH3OH(g)Predict whether reactants or products will be favored at equilibrium in the reaction above.
The amino acid alanine has two isomers, α-alanine and β-alanine. When equal masses of these two compounds are dissolved in equal amounts of a solvent, the solution of α-alanine freezes at the lowest temperature. Which form, α-alanine or β-alanine, has the larger equilibrium constant for ionization (HX ⇌ H + + X−) ?
You may want to reference (Pages 680 - 684) Section 15.3 while completing this problem.Use the reactions below and their equilibrium constants to predict the equilibrium constant for the reaction 2 A(s) ⇌ 3 D(g).A(s) ⇌ 1/2  ightleftharpoons;large{frac{1}{2}}B(g) + C(g);  K1 = 0.03343 D(g) ⇌  ightleftharpoons; B(g) + 2 C(g);  K2 = 2.35
Carbon monoxide replaces oxygen in oxygenated hemoglobin according to the reaction:HbO2(aq) + CO(aq) ⇌ HbCO(aq) + O2(aq)Use the reactions and associated equilibrium constants at body temperature given here to find the equilibrium constant for the reaction just shown.Hb(aq) + O2(aq) ⇌ HbO2(aq); Kc = 1.8Hb(aq) + CO(aq) ⇌ HbCO(aq); Kc = 306
You may want to reference (Page 683) Section 15.3 while completing this problem.Use the data shown here to find the equilibrium constant (Kc) for the reaction A(g) ⇌ 2B(g) + C(g).A(g) ⇌ 2X(g) + C(g); Kc = 2.01B(g) ⇌ X(g); Kc = 23.6
You may want to reference (Pages 680 - 684) section 15.3 while completing this problem.The reaction has an equilibrium constant Kp = 2.2 x 106 at 298 K: 2 COF2(g) ⇌ CO2(g) + CF4(g)Calculate Kp for the reaction: 6COF2(g) ⇌ 3CO2(g) + 3CF4(g)
You may want to reference (Pages 680 - 684) section 15.3 while completing this problem.The reaction has an equilibrium constant Kp = 2.2 x 106 at 298 K: 2 COF2(g) ⇌ CO2(g) + CF4(g)Calculate Kp for the reaction: 2CO2(g) + 2CF4(g) ⇌ 4COF2(g)
You may want to reference (Pages 680 - 684) Section 15.3 while completing this problem.Consider the chemical equation and equilibrium constant at 25oC: 2COF2(g) ⇌ CO2(g) + CF4(g); K = 2.2 x 106Calculate the equilibrium constant for the following reaction at 25oC: 2CO2(g) + 2CF4(g) ⇌ 4COF2(g); K′ = ? m 2CO_2(g) + 2CF_4(g); ightleftharpoons; 4COF_2(g)
The reactions shown here can be combined to make the overall reaction C(s) + H2O(g) ⇌ CO(g) + H2(g) by reversing some and/or dividing all the coefficients by a number.a. C(s) + O2( g) ⇌ CO2(g); K = 1.363 x 1069b. 2H2(g) + O2(g) ⇌ 2H2O(g); K = 1.389 x 1080c. 2CO(g) + O2(g) ⇌ 2CO2(g); K = 1.363 1069 ;;;K = 1.477 imes 10^{90}Select the correct formula you would use to determine K.
The reactions shown here can be combined to make the overall reaction C(s) + H2O(g) ⇌ CO(g) + H2(g) by reversing some and/or dividing all the coefficients by a number.a. C(s) + O2( g) ⇌ CO2(g); K = 1.363 x 1069b. 2H2(g) + O2(g) ⇌ 2H2O(g); K = 1.389 x 1080c. 2CO(g) + O2(g) ⇌ 2CO2(g); K = 1.363 1069 ;;;K = 1.477 imes 10^{90}Determine the value of K.
The reaction A(g) ⇌ 2 B(g) has an equilibrium constant of K = 0.055. What is the equilibrium constant for the reaction large{{ m B(g)} ightleftharpoons frac{1}{2}{ m A(g)}}B(g) ⇌ 1/2 A(g)?
The reaction below has an equilibrium constant of Kp = 2.26 x 104 at 298 K:CO(g) + 2 H2(g) ⇌ CH3OH(g)Calculate Kp for the reaction below.CH3OH(g) ⇌ CO(g) + 2 H2(g)
The reaction below has an equilibrium constant of Kp = 2.26 x 104 at 298 K:CO(g) + 2 H2(g) ⇌ CH3OH(g)Calculate Kp for the reaction below.2 CH3OH(g) ⇌ 2 CO(g) + 4 H2(g)
Consider the following reactions and their respective equilibrium constants:NO(g) + 1/2 Br2(g) ⇌ NOBr(g); Kp = 5.32 NO(g) ⇌ N2(g) + O2(g); Kp = 2.1 x 1030Use these reactions and their equilibrium constants to predict the equilibrium constant for the following reaction:N2(g) + O2(g) + Br2(g) ⇌ 2 NOBr(g)
At 375.0 K. the value Kp for the combination reaction of N2 and H2 that produces NH3 gas is 0 0061 What is the equilibrium constant for the decomposition reaction of NH3 at the same temperature that produces N2 and H2?
If Kc = 0.0055 for the reactionN2 (g) + 3 H2 (g) 2 NH3 (g)runs at 355.0 K, what is Kc at 355.0 K for the reaction:1/3 N2 (g) + H2 (g) 2/3 NH3 (g)
For the dissociation of I2 (g) at about 1200°C, I2 (g) ⇌ 2 I (g), Kc + 1.1 x10-2. What volume flask should we use if we want 0.42 mol I to be present for every 1.00 mol I2 at equilibrium? Express your answer using two significant figures.
For A + 2B ⇌ 2C      Kc = 2.99 For 2C ⇌ D              Kc = 0.232 Calculate the value of the equilibrium constant for the reaction D ⇌ A + 2B 
At a given temperature, the equilibrium constant for the reactionCO(g) + H2O(g) ⇌ CO2(g) + H2(g)is 6.00 x 102. What is the equilibrium constant, at the same temperature, for the following reaction?H2(g) + CO2(g) ⇌ H2O(g) + CO(g) 
Calculate the value of Kp for the equation C(s) + CO2(g) ⇌ 2CO(g) Kp = ?given that at a certain temperatureC(s) + 2H2O(g) ⇌ CO2(g) + 2H2(g) Kp1 = 3.63H2(g) + CO2(g) ⇌ H2O(g) + CO(g) + Kp2 = 0.765Kp = ?
For chemical reactions involving ideal gases, the equilibrium constant K can be expressed either in terms of the concentrations of the gases (in M) or as a function of the partial pressures of the gases (in atmospheres). In the latter case, the equilibrium constant is denoted as Kp to distinguish it from the concentration-based equilibrium constant K. For the reaction 2CH4 (g) ⇌ C2H2(g) + 3H2(g)K = 0.130 at 1689°C. What is Kp for the reaction at this temperature?For the reaction N2(g) + 3H2(g) ⇌ 2NH3(g)Kp = 2.35 x 10-3 at 311°C  K = 0.130 at 1689 °C. What is Kp for the reaction at this temperature?
The equilibrium constant for the chemical equation N2 (g) + 3H2 (g) ⇌ 2NH3 (g) is Kp = 1 01 at 209°C. Calculate the value of the Kc for the reaction at 209°C.
The equilibrium constant for the chemical equation N2(g) + 3H2 (g) ⇌ 2NH3(g) is K p = 3.50 at 201°C. Calculate the value of the Kc for the reaction at 201°C.
For the system NH2OH + CH3NH3+ ⇌ CH3NH2 + NH3OH+ the position of the equilibrium lies to the left. Which is the strongest acid in the system? (a) NH2OH(b)  CH3NH3+ (c) CH3NH2 (d) NH3OH+ (e) NH2OH and CH3NH3+ are equal in acid strength, and are the strongest acids in the system
The equilibrium constant for the following reaction is 5.93 at 111°C. 2CH2Cl2 (g) ⇌ CH4 (g) + CCl4 (g)       K = 5.93 at 111°CCalculate the equilibrium constant for the following reactions at 111 °C. (a) CH4 (g) + CCl4 (g) ⇌ 2CH2Cl2 (g)      K = ?(b) CH2Cl2 (g) ⇌ 1/2CH4 (g) + 1/2CCl4 (g)    K = ?
At 351 K, this reaction has a Kc value of 0.0679. 2X(g) + 2Y(g) ⇌ Z(g) Calculate Kp at 351 K. Kp = 
For A + 2B ⇌ 2C           K  c = 2.65 For 2C ⇌ D                                        K      c = 0.162 Calculate the value of the equilibrium constant for the reaction D ⇌ A + 2B 
The equilibrium constant for the chemical equation N2 (g) + 3H2 (g) ⇌ 2NH3 (g)is Kp = 13.8 at 187°C. Calculate the value of the K c for the reaction at 187°C.
The Keq for the equillibrium below is 5.4 x 1013 at 480°C.2NO (g) + O2 (g) ⇌ 2NO2 (g)What is the value of Keq at this temperature for the following reaction?4NO (g) + 2O2 (g) ⇌ 4NO2 (g)
A solution is made that is 1.0 M in A and 1.0 M in B, A and B then react: A(aq) + B(aq) ⇌ C(aq) + D(aq) What would the equilibrium concentration of A be with each of the following equilibrium constants? Note that ~0 means that the concentration is very small.
For the reversible reaction which K values would indicate that there is more B than A at equilibrium?
What determines the amount of product formed in an irreversible reaction? a. The volume of the solution b. The equilibrium state c. The amount of limiting reactant present d. The rate of the reverse reaction
The steam reformation reaction is an important source of H2 (at 750°C): CH4 (g) + H2O (g) ⇌ CO (g) + 3H2 (g) Use the following information to calculate Kp (750°C): H2 (g) + 1/2O2 (g) ⇌ H2O (g)                        K1 = 1.56 x 1023 2CH4 (g) + O2 (g) ⇌ 2CO (g) + 4H2 (g)        K2 = 5.90 x 1015
Calculate the value of Kp for the equationC (s) + CO2 (g) ⇌ 2 CO (g) Kp = ?Given that at a certain temperatureC (s) + 2 H2O (g) ⇌ CO2 (g) + 2 H2 (g) Kp1 = 3.97H2 (g) + CO2 (g) ⇌ H2O (g) + CO (g) Kp2 = 0.623
For the reversible reactionA(g) ⇌ B(g) Which K value would indicate that there is more B than A at equilibrium?A. K = 9x10-9B. K = 0.2C. K = 9000D. K = 9x109
Calculate the value of the equilibrium constant for the reaction:D in equilibrium with A + 2 B, A + 2 B in equilibrium with 2 C, K  c = 2.35, 2C in equilibrium with D, Kc = 0.182