Ch.13 - Chemical KineticsSee 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
General Rate

Concept #1: Understanding Average or General Rate. 

General or Average Rate is the change in the concentration of a compound over a period of time.

Example #1: The following equation shows the production of NO and H2O by oxidation of ammonia. 

4 NH3 (g) +  5 O2 (g)   →  4 NO (g)  + 6 H2O (l)             

a. What is the average rate of each compound in the balanced equation? 

Example #2: b) What is the rate of NH3 in the reaction between 2 and 6 minutes at 40oC? 

Example #3: c) Determine the instantaneous rate of the following reaction.

Stoichiometric Rate

In a stoichiometry based question we are accustomed to doing a mole-to-mole comparison. Now in Chemical Kinetics, we will do instead a rate-to-rate comparison. 

Example #4: The decomposition of dinitrogen pentoxide is described by the chemical equation:

2 N2O5 (g)   --->  4 NO2 (g)  +  O2 (g)

If the rate of disappearance or decomposition of O2 is equal to 2.20 M/min at a particular moment, what is the rate of appearance or formation of N2O5 at that moment? 

Practice: The formation of alumina, Al2O3, can be illustrated by the reaction below: 4 Al (s) + 3 O2 (g) ----> 2 Al2O3 (s). At 750 K it takes 267 seconds for the initial concentration of Al2O3 to increase from 6.18 E-5 M to 5.11 E-4 M. What is the rate of Al? 

Additional Problems
The combustion of propanol, C3H7OH (l), to produce carbon dioxide and water vapor is a highly exothermic process 2 C3H7OH (l) + 9 O2 (g) → 6 CO2 (g) + 8 H2O (g) The following data table shows the change in concentration of O 2 over time. Use this data to determine the rate of evolution of water vapor, H2O(g), in the reaction between 10 and 30 seconds. Time in seconds                      Concentration of O2 (M)           0                                           2.48 x 10      -3           10                                          1.26 x 10      -3          20                                          8.98 x 10      -4          30                                          7.17 x 10      -4          40                                          6.32 x 10      -4          50                                          5.98 x 10      -4          60                                          5.71 x 10      -4 a. 2.73 x 10 -5 b. 2.41 x 10 -5 c. 4.83 x 10 -4 d. 3.05 x 10 -5 e. 6.11 x 10 -4  
For the reaction given, the FeCl3 changes from 1.000 M to 0.444 M in the first 10 seconds. Calculate the average rate in the first 10 seconds.  2 FeCl3 (s) → 2 Fe (s) + 3 Cl2 (g)  a. 0.0384 M/s b. 0.210 M/s c. 0.0278 M/s d. 0.0874 M/s e. 0.568 M/s 
Consider the following hypothetical reaction 4A (g) + 2B (g) → 3C (g) + D (g) Which of the following statement(s) is/are correct? i. The rate B disappears is twice (2 times) the rate that D appears. ii. The rate A disappears is twice (2 times) the rate that B disappears. iii. The rate C appears is one third (1/3 times) the rate that D appears.   A. i only B. ii only C. i and ii D. ii and iii E. i and iii
Consider the reaction: 2 NO(g) + O2(g) →2 NO2(g) If the instantaneous rate of reaction of nitric oxide (NO) is ‐ 0.016 M/s, at what rate is molecular oxygen reacting A) ‐0.016 M/s B) ‐0.032 M/s C) ‐0.008 M/s D) +0.016 M/s E) +0.032 M/s    
Given the following balanced equation, determine the rate of reaction with respect to [NOCl]. If the rate of Cl2 loss is 4.84 x 10-2 M/s, what is the rate of formation of NOCl? 2 NO(g) + Cl2(g) → 2 NOCl(g) A) 4.84 x 10-2 M/s B) 2.42 x 10-2​ M/s C) 1.45 x 10-1​ M/s D) 9.68 x 10-2​ M/s E) 1.61 x 10-2​ M/s
Given the following balanced equation, determine the rate of reaction with respect to [SO2]. 2 SO2 (g) + O2 (g) → 2 SO3 (g) A. Rate = -1/2 Δ[SO2]/Δt B. Rate = +1/2 Δ[SO2]/Δt C. Rate = - Δ[SO2]/Δt D. Rate = + 2Δ[SO2]/Δt E. It is not possible to determine without more information.
The rate of decrease in N2H4 partial pressure in a closed reaction vessel is 75 torr/h. What is the rate of change of ammonia partial pressures and total pressure in vessel? N2H4(g) + H2(g) → 2 NH3(g) a) 75 torr, 300 torr b) 150 torr, 300 torr c) 150 torr, 150 torr d) 150 torr, 0 torr e) 75 torr, 0 torr
Consider this reaction. 4 NH3 (g) + 3 O2 (g) ⇌ 2 N2 (g) + 6 H2O (l) If the rate formation of N2 is 0.10 M•s-1, what is the corresponding rate of dissapearance of O 2? (A) 1.5 M•s-1 (B) 0.30 M•s-1 (C) 0.15 M•s-1 (D) 0.10 M•s-1
The balanced equation for the reaction of bromate ion with bromide in acidic solution is given by: At a particular instant in time, the value of −Δ[Br -]/Δt is 2.0 x 10-3 mol/L s. What is the value of Δ[Br2]/Δt in the same units? A. 1.2 x 10-3 B. 6.0 x 10-3 C. 3.3 x 10-3 D. 3.3 x 10-5 E. 2.0 x 10-3
For the reaction BrO3- + 5Br - + 6H+ → 3Br2 + 3H2O at particular time, -Δ[BrO3-]/ Δt = 1.5 x 10 -2 M/s. What is -Δ [Br-]/ Δt at the same instant? A) 13 M/s B) 7.5 x 10-2 M/s C) 1.5 x 10-2 M/s D) 3.0 x 10-3 M/s E) 330 M/s
For the reaction A + 2B → C, which expression is correct? A) Δ[C]/ Δt = Δ [A]/ Δt B) Δ[C]/ Δt = 2Δ [B]/ Δt C) Δ[C]/ Δt = -2Δ [B]/ Δt D) Δ[C]/ Δt = -(1/2)Δ [B]/ Δt E) Δ[C]/ Δt = -(1/2)Δ [A]/ Δt
Using the format given in your text, which of the following rate equalities is correct for the following reaction? 4 NH3(g) + 7 O2 (g) → 4 NO2(g) + 6 H2O(g)
Consider the reaction N2(g) + 3H2(g) → 2NH3(g) Suppose at a particular moment during the reaction molecular hydrogen is reacting at a rate of 0.084 M/s. a. At what rate is ammonia being formed? b. At what rate is molecular nitrogen reacting? c. What is the average rate of the reaction?
Based on your knowledge of general rates answer the following question. 
For the reaction, 4PH3(g) → P4(g) + 6H2(g) the rate of reaction is 0.018 moles L−1s−1, what is the rate of formation of H 2? a) 0.018 moles L−1s−1 b) 0.072 moles L−1s−1 c) 0.003 moles L−1s−1 d) 0.0045 moles L−1s−1 e) 0.108 moles L−1s−1
Under certain conditions, the average rate of appearance of oxygen gas in the reaction 2O3(g) → 3O2(g) is 1.2 x 10–3 atm•s–1. What is the average rate, expressed in atm•s –1, for the disappearance of O3? (A) 8.0 x 10–4 (B) 1.2 x 10–3 (C) 1.8 x 10–3 (D) 5.3 x 10–3
What is the balanced reaction for the following rate relationships?    
Given the following balanced equation, if the rate of Cl2 loss is 4.24 × 10-2 M/s, what is the rate of formation of NOCl?  
Which statement is true of the reaction below?  2 A (g) + B (g) → C (g) + 2 D (g) a) B is lost at twice the rate that A is lost b) D is gained at twice the rate that A is lost c) A is lost at twice the rate that B is lost d) C is gained at twice the rate that D is gained e) The rate law must be known to answer this question  
Consider the following chemical equation 12 HCIO4 (aq) + P4O10 (g) --> 4 H3PO4 (aq) + 6 Cl2O7 (g) If the rate of the appearance with respect to H3PO4 is 5.72 x 10-5 M min-1, what is the rate of the appearance of Cl2O7? A. 3.81 x 10-5 Mmin-1 B. 8.58 x 10-5 Mmin-1 C. 2.29 x 10-4 Mmin-1 D. 1.14 x 10-4 Mmin-1 E. 2.86 x 10-5 Mmin-1
For reaction 5 O2 (g) + 4 NH3 (g) → 4 NO (g) + 6 H2O (g) if NH3 is being consumed at a rate of 0.50 M • s –1, at what rate is H2O being formed? a) 0.33 M•s–1 b) 0.50 M•s–1 c) 0.75 M•s–1 d) 3.0 M•s–1
What units are typically used to express the rate of a reaction?
Why is the reaction rate for reactants defined as the negative of the change in reactant concentration with respect to time, whereas for products it is defined as the change in reactant concentration with respect to time (with a positive sign)?
Consider the following reaction and data:H2 + 2ICl → 2HCl + I 2Time (s)                I  2 concentration (M)    5                              1.11   15                             1.83a. What is the average rate of formation of I 2? Express your answer to three decimal places and include the appropriate units.b. Based on your answer to Part a, what is the average rate of formation of HCl? Express your answer to three decimal places and include the appropriate units.c. Based on your answer to Part a or b, what is the average rate of change of H  2? Remember that reactant concentrations decrease over time.Express your answer to three decimal places and include the appropriate units.
Consider the reaction:8H2S(g) + 4O2 → 8H2O(g) + S8(g)Δ[H2S]/Δt= - 0.019 M/sa. Find Δ[O2]/Δtb. Find Δ[H2O]/Δtc. Find Δ[S8]/Δtd. Find the rate of the reaction.
Consider the reaction: 8H2S(g) + 4O2(g) → 8H2O(g) + S8(g)            Δ[H 2S]/Δt = -0.031 M/s a. Find Δ[O2]/Δt.b. Find Δ[H2O]/Δt.c. Find Δ[S8]/Δt.d. Find the rate of the reaction.
Consider the reaction 5Br−(aq) + BrO3−(aq) + 6H+(aq) → 3Br2(aq) + 3H2O(l) The average rate of consumption of Br− is 2.06 × 10−4 M/s over the first two minutes. What is the average rate of formation of Br2 during the same time interval? Express your answer with the appropriate units.
The decomposition of N2O5 can be described by the equation: 2N2O5 (soln) →  4NO2 (soln) + O 2 (g)   Given this data for the reaction at 45 degrees C in carbon tetrachloride solution, calculate the average rate for each successive time interval. t(s)                [N2O5] (M) 0                    2.10 195                1.86 556                1.48 825                1.25 Interval: 0 s to 195 s Reaction rate= _____M/s 195 s to 556 s Reaction rate= _____M/s 556 s to 825 s Reaction rate= _____M/s
Consider the reaction: 8H2S(g) + 4O2(g) → 8H2O(g) + S8(g)        Δ[H2S]/Δt = -0.071 M/s a. Find Δ[O2]/Δt. Express your answer to two significant figures and include the appropriate units. b. Find Δ[H2O]/Δt. Express your answer to two significant figures and include the appropriate units. c. Find Δ[S8]/Δt. Express your answer to two significant figures and include the appropriate units. d. Find the rate of the reaction. Express your answer to two significant figures and include the appropriate units.
For the reaction,2NO(g) + 2H2(g) → N2(g) + 2H2O(g)at a particular time the concentration of NO was decreasing at an instantaneous rate of 0.54 moles L−1s-1. What is the rate of reaction?a) 0.54 moles L−1s-1b) 0.27 moles L−1s-1c) 2.16 moles L−1s-1d) 1.08 moles L−1s-1e) 0.135 moles L−1s-1
Complete the expressions for the rate of appearance of products and the rate of disappearance of reactants in each of the following reactions. NOTE: add only minus signs and fractions where appropriate. a) Cl2O2(g) → 2ClO(g) b) N2O5(g) → NO2(g) + NO3(g)
Consider the reaction: 2H3PO4 → P2O5 + 3H2O Using the information in the following table,  Time (s)                          P  2O5 (M) 0                                           0 10                                  1.30 x 10    -3 20                                  4.30 x 10    -3 30                                  6.10 x 10    -3 40                                  7.30 x 10    -3 50                                  7.90 x 10    -3 i) Calculate the average rate of formation of P2O5 between 10.0 and 40.0 s.   ii) Rate of formation of P2O5 = 2.00 x 10-4 M/ s. What is the average rate of decomposition of H3PO4 between 10.0 and 40.0 s?
Consider the following reaction: NO2(g) → NO(g) + 1/2 O2(g). The following data were collected for the concentration of NO2 as a function of time. Express your answer using two significant figures.a. What is the average rate of the reaction between 10 and 20?b. What is the average rate of the reaction between 50 and 60 ?c. What is the rate of formation of NO2 between 50 and 60 ?
Write the general rate equation for the following reaction, as written, for each of the components C2H6(I) +7/2O2(g) → 2CO2(q) + 3H2O(I)  
In the nuclear industry, chlorine trifluoride is used to prepare uranium hexafluoride, a volatile compound of uranium used in the separation of uranium isotopes. Chlorine trifluoride is prepared by the reactionCl2 (g) + 3 F2 (g) ⟶ 2 ClF3 (g).Write the equation that relates the rate expressions for this reaction in terms of the disappearance of Cl2 and F2 and the formation of ClF3.
You may want to reference (Pages 625 - 628) section 14.2 while completing this problem.Consider the following reaction: 2 N2O(g) → 2 N2(g) + O2(g). Express the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Consider the following reaction: 2 HBr(g) → H2(g) + Br2(g)Express the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Consider the reaction: 2 A(g) + B(g) → 3 C(g). Determine the expression for the rate of the reaction with respect to each of the reactants and products.
An average reaction rate is calculated as the change in the concentration of reactants or products over a period of time in the course of the reaction. An instantaneous reaction rate is the rate at a particular moment in the reaction and is usually determined graphically. The reaction of compound A forming compound B was studied and the following data were collected: Time (s)                    [A] (M) 0.                               0.184 200.                           0.129 500.                           0.069  800.                           0.031 1200.                         0.019 1500.                         0.016 a. What is the average reaction rate between 0 s and 1500 s? b. What is the average reaction rate between 500 s and 1200 s? c. What is the instantaneous rate of the reaction at t = 800 s?
You may want to reference (Page 624) Section 14.2 while completing this problem.This graph shows the concentration of the reactant A in the reaction A.Determine the average rate of the reaction between 0 and 10 seconds.
A study of the rate of dimerization of C4H6 gave the data shown in the table: 2 C4H6 ⟶ C8H12(a) Determine the average rate of dimerization between 0 s and 1600 s, and between 1600 s and 3200 s.
A study of the rate of the reaction represented as 2A ⟶ B gave the following data:(a) Determine the average rate of disappearance of A between 0.0 s and 10.0 s, and between 10.0 s and 20.0 s.
You may want to reference (Pages 625 - 628) section 14.2 while completing this problem.Consider the following reaction: 2 N2O(g) → 2 N2(g) + O2(g). In the first 13.0 s of the reaction, 1.8 × 10−2 mol of O2 is produced in a reaction vessel with a volume of 0.380 L. What is the average rate of the reaction over this time interval?
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the following reaction: NO2(g) → NO(g) + 1/2 O2(g). The following data were collected for the concentration of NO2 as a function of time: Time (s)  [NO2] (M) 01.000100.951200.904300.860400.818500.778600.740700.704800.670900.6371000.606What is the average rate of the reaction between 10 and 20 s?
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the following reaction: NO2(g) → NO(g) + 1/2 O2(g). The following data were collected for the concentration of NO2 as a function of time: Time (s)  [NO2] (M) 01.000100.951200.904300.860400.818500.778600.740700.704800.670900.6371000.606What is the rate of formation of O2 between 50 and 60 s?
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the following reaction: NO2(g) → NO(g) + 1/2 O2(g). The following data were collected for the concentration of NO2 as a function of time: Time (s)  [NO2] (M) 01.000100.951200.904300.860400.818500.778600.740700.704800.670900.6371000.606What is the average rate of the reaction between 50 and 60 s?
Consider the following reaction: 2 HBr(g) → H2(g) + Br2(g)In the first 23.0 s of this reaction, the concentration of HBr dropped from 0.570 M to 0.482 M. Calculate the average rate of the reaction in this time interval.
Consider the following reaction: C4H8(g) → 2 C2H4(g). The following data were collected for the concentration of C4H8 as a function of time: Time (s)  [C4H8] (M) 01.000100.913200.835300.763400.697500.637What is the average rate of the reaction between 0 and 10 s?
Consider the following reaction: C4H8(g) → 2 C2H4(g). The following data were collected for the concentration of C4H8 as a function of time: Time (s)  [C4H8] (M) 01.000100.913200.835300.763400.697500.637What is the rate of formation of C2H4 between 20 and 30 s?
Consider the following reaction: C4H8(g) → 2 C2H4(g). The following data were collected for the concentration of C4H8 as a function of time: Time (s)  [C4H8] (M) 01.000100.913200.835300.763400.697500.637What is the average rate of the reaction between 40 and 50 s?
Consider the following reaction: H2(g) + Br2(g) → 2HBr. The graph below shows the concentration of Br2 as a function of time.Use the graph to calculate the average rate of the reaction between 0 and 25 s.
Consider the following reaction: 2 H2O2(aq) → 2 H2O(l) + O2(g). The graph shows the concentration of H2O2 as a function of time. Use the graph to calculate the following.The average rate of the reaction between 10 and 20 s.
Consider the following reaction: 2 H2O2(aq) → 2 H2O(l) + O2(g). The graph shows the concentration of H2O2 as a function of time. Use the graph to calculate the following.If the initial volume of the H2O2 solution is 1.6 L, what total amount of O2 (in moles) is formed in the first 50 s of reaction?
The aqueous reaction of KOH with HBr is: KOH(aq) + HBr(aq) → KBr(aq) + H2O(l) At the start of such a reaction, the concentration of KOH(aq) is 0.275M. After 3.05 seconds the concentration is observed to be 0.0557M KOH(aq). What is the rate of the reaction?  
You may want to reference (Page 624) Section 14.2 while completing this problem.Dinitrogen monoxide decomposes into nitrogen and oxygen when heated. The initial rate of the reaction is 2.4 × 10−2 M/s. What is the initial rate of change of the concentration of N2O (that is, Δ[N2O]/Δt)?2 N2O(g) → 2 N2(g) + O2(g)
Consider the following reaction in aqueous solution:5 Br−(aq) + BrO3 −(aq) + 6 H+(aq) ⟶ 3 Br2 (aq) + 3 H2O(l)If the rate of disappearance of Br– (aq) at a particular moment during the reaction is 3.5 × 10−4 M s−1, what is the rate of appearance of Br2(aq) at that moment?
For the reaction A + 2B → C under a given set of conditions, the initial rate is 0.100 M/s. What is Δ[B]/Δt under the same conditions?
Consider the reaction: 2 A(g) + B(g) → 3 C(g). When A is changing at a rate of -0.140 M s-1, how fast is B changing?
Consider the reaction: Cl2(g) + 3F2(g) → 2ClF3(g).Given that Δ[Cl2]/Δt = -0.054 M/s. Find Δ[F2]/Δt
Consider the reaction: Cl2(g) + 3F2(g) → 2ClF3(g).Given that Δ[Cl2]/t = -0.054 M/s. Find Δ[ClF3]/Δt
Consider the reaction: Cl2(g) + 3F2(g) → 2ClF3(g).Given that Δ[Cl2]/Δt = -0.054 M/s. Find the rate of the reaction.
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the reaction: 8 H2S(g) + 4 O2(g) → 8 H2O(g) + S8(g)Given that Δ[H2S]/Δt = -0.049 M/s. Find Δ[O2]/Δt.
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the reaction: 8 H2S(g) + 4 O2(g) → 8 H2O(g) + S8(g)Given that Δ[H2S]/Δt = -0.049 M/s. Find Δ[H2O]/Δt.
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the reaction: 8 H2S(g) + 4 O2(g) → 8 H2O(g) + S8(g)Given that Δ[H2S]/Δt = -0.049 M/s. Find Δ[S8]/Δt.
You may want to reference (Pages 625 - 628) Section 14.2 while completing this problem.Consider the reaction: 8 H2S(g) + 4 O2(g) → 8 H2O(g) + S8(g)Given that Δ[H2S]/Δt = -0.049 M/s. Find the rate of the reaction.
Consider the following reaction: H2(g) + Br2(g) → 2HBr. The graph below shows the concentration of Br2 as a function of time.Make a rough sketch of a curve representing the concentration of HBr as a function of time. Assume that the initial concentration of HBr is zero.
At a given temperature, the elementary reaction A ⇌ B in the forward direction is first order in A with a rate constant of 4.30 x 102 s-1. The reverse reaction is first order in B and the rate constant is 5.70 x 102 s-1.What is the value of the equilibrium constant for the reaction A  ⇌ B at this temperature? What is the value of the equilibrium constant for the reaction B ⇌ A at this temperature? 
Consider the following reaction: 2HBr (g) → H2 (g) + Br2 (g) Part B In the first 23.0 s of this reaction the of HBr dropped from 0.550 M to 0.457 M. Calculated the average rate of the reaction in this time interval. Express your answer using two significant figures. Part CIf the volume of the reaction in part (b) was 1.50 L. what amount of Br2 (in moles) was formed during the 15.0 is of the reaction?Express your answer using two significant figures.
In the reaction 2N2O5 → 4NO2 + O2 given that the rate law is v = k[N 2O5] where v is the reaction rate or reaction velocity, calculate the rate of formation of NO 2 if the instantaneous rate of reaction is 1.7 x 10-6 mol L-1 s-1. 
The decomposition of N2O5 can be described by the equation2N2O5 (soln) → 4NO2 (soln) + O2 (g)Given these data for the reaction at 45° C in carbon tetrachloride solution, calculate the average rate of reaction for each successive time interval.
a. If Δ[NO3] / Δt is -21.51 x 104 mM/min in the following reaction, what is the rate of appearance of NO2? NO3(g) + NO(g) → 2NO(g) b. What is the rate of change in [NO2] in the following reaction if Δ[NO3] / Δt is -23.36 x 10-1 mM/min? 2N3(g) → 2NO2(g) + O2(g)
The rate of the following reaction is 0.720 M/s. What is the relative rate of each species in the reaction?
A reaction generates chlorine gas (Cl 2) as a product. The reactants are mixed and sealed in a 500.-mL container. After 30.0 minutes, 2.05 x 10-3 mol of Cl2 has been generated. Calculate the average rate of the reaction. 
In a study of the decomposition of nitrosyl bromide at 10°C.NOBr → NO + 1/2 Br2 the following data were obtained: (1) The observed half life for this reaction when the starting concentration is 0.311 M is _________ s and when the starting concentration is 0.156 M is ________s. (2) The average Δ(1/[NOBr])/Δt from t = 0 s to t = 5.00 s is __________ M-1 s-1. The average Δ(1/[NOBr])/Δt from t = 5.00 s to t = 15.0 s is ___________M-1 s-1. 
The following chemical reaction was performed and the concentration of CCl4 was measured over time. Cl2 (g) + CHCl3 (g) → HCl (g) + CCI (g) The [CCl4] after 9 s was 0.153 mo/L. After 138 s, the [CCl4] was 0.374 mol/L. Calculate the rate of reaction.
The decomposition of dinitrogen pentoxide is described by the chemical equation 2N2O5(g) → 4NO2(g) + O2(g) If the rate of appearance of NO 2 is equal to 0.78 mol/min at a particular moment, what is the rate of appearance of O2 at that moment? 
For the gas phase decomposition of dimethyl ether at 500°C, the rate of the reaction is determined by measuring the appearance of CH4. CH3OCH3 → CH4 + H2 + CO At the beginning of the reaction, the concentration of CH 4 is 0 M. After 26.3 min the concentration has increased to 4.53 x 10-2 M. What is the rate of the reaction? 
The following chemical reaction was performed and the concentration of HCl was measured over time. Cl2 (g) + CHCl3 (g) → HCl (g) + CCl4 (g) The [HCI] after 15 s was 0.184 mol/L. After 138 s, the [HCI] was 0.451 mollL. Calculate the rate of reaction.
Suppose a small lake is contaminated with an insecticide that decomposes with time. An analysis done in June shows the decomposition product concentration to be 3.13 x 10-4 mol/L. An analysis done 35 days later shows the concentration of decomposition product to be 7.33 x 10-4 mol/L. Assume the lake volume remains constant and calculate the average rate of decomposition of the insecticide. 
Consider the decomposition of dinitrogen pentoxide: 2 N2O5 (g) → 4 NO2 (g) + O2 (g) The following data were collected for the reaction at a given temperature: What is the average rate of formation of NO2 after 4 seconds of reaction? Be sure to include a minus sign if your calculated result is negative. Your answer should be expressed in units of M/s and with the correct number of significant digits, but do not include the units in your submitted answer.
Consider the reaction 8H2S(g) + 4O2 (g) → 8H2O(g) + S8 (g) Δ[H2S]/Δt = -0.031 M/s Part AFind Δ[O2]/Δt. Express your to two significant figure and include the appropriate units. Part BFind Δ[H2O]/Δt. Express your answer to two significant figures and include the appropriate units. Part CFind Δ[S8]/Δt. Express your answer to two significant figure and include the appropriate units. Part D Find the rate of the reaction. Express your answer to two significant figure and include the appropriate units.
Consider the reaction, 2NH3 (g) → N2 (g) + 3H2( g) If the rate of hydrogen production is 0.030 mol L-1 s-1, then the rate of nitrogen production is a. 0.030 mol L-1 s-1b. 0.010 mol L-1 s-1c. 0.020 mol L-1 s-1d. 0.090 mol L-1 s-1
The decomposition of N2O5 can be described by the equation2N2O5 → 4NO2 + O2Given these data for the reaction at 45 °C in carbon tetrachloride solution, calculate the average rate of reaction for each successive time interval.t(s)       [N2O5]0             2.04135         1.87536         1.46795          1.24i) Reaction rate from 0-135 is ?ii) Reaction rate from 135-536 is ?iii) Reaction rate from 536-795 is ?
The decomposition of N2O5 can be described by the equation.2N2O5 (soln) →  4NO2 (soln) + O2 (g)Given this data for the reaction at 45°C in carbon tetrachloride solution, calculate the average rate for each successive time interval.t(s)                [N2O5] (M)0                    2.10195                1.86556                1.48825                1.25i) Interval: 0 s to 195 sReaction rate= _____M/sii) Interval: 195 s to 556 sReaction rate= _____M/siii) Interval: 556 s to 825 sReaction rate= _____M/s