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Problem 48a,b
Indicate the order of reaction consistent with each observation.
a. The half-life of the reaction gets shorter as the initial concentration is increased.
b. A plot of the natural log of the concentration of the reactant versus time yields a straight line.
Problem 39c,d,e,f
A reaction in which A, B, and C react to form products is first order in A, second order in B, and zero order in C c. By what factor does the reaction rate change if [A] is doubled (and the other reactant concentrations are held constant)? d. By what factor does the reaction rate change if [B] is doubled (and the other reactant concentrations are held constant)? e. By what factor does the reaction rate change if [C] is doubled? f. By what factor does the reaction rate change if the concentrations of all three reactants are doubled?
Problem 40c,d,e,f
A reaction in which A, B, and C react to form products is zero order in A, one-half order in B, and second order in C. c. By what factor does the reaction rate change if [A] is doubled (and the other reactant concentrations are held constant)? d. By what factor does the reaction rate change if [B] is doubled? e. By what factor does the reaction rate change if [C] is doubled? f. By what factor does the reaction rate change if [C] is doubled (and the other reactant concentrations are held constant)?
- The tabulated data show the concentration of N2O5 versus time for this reaction: N2O5(g) → NO3(g) + NO2(g). Time (s) [N2O5] (M): 0 - 1.000, 25 - 0.822, 50 - 0.677, 75 - 0.557, 100 - 0.458, 125 - 0.377, 150 - 0.310, 175 - 0.255, 200 - 0.210. Determine the order of the reaction and the value of the rate constant. Predict the concentration of N2O5 at 250 s.
Problem 5
- Is the question about drawing a diagram that depicts the energy progression of an endothermic chemical reaction with an activation energy twice the value of the reaction's enthalpy change formulated correctly?
Problem 6
- A reaction has a rate constant of 0.000122 s⁻¹ at 27 °C and 0.228 s⁻¹ at 77 °C. a. Determine the activation barrier for the reaction.
Problem 7
- Cyclopropane (C3H6) reacts to form propene (C3H6) in the gas phase. The reaction is first order in cyclopropane and has a rate constant of 5.87 * 10^-4 s^-1 at 485 °C. If a 2.5-L reaction vessel initially contains 722 torr of cyclopropane at 485 °C, how long will it take for the partial pressure of cyclopropane to drop to below 1.00 * 10^2 torr?
Problem 9
Problem 25a
Consider the reaction:
2 HBr (g) → H2 (g) + Br2 (g)
a. Express the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Problem 25b
Consider the reaction:
2 HBr (g) → H2 (g) + Br2 (g)
b. In the first 25.0 s of this reaction, the concentration of HBr dropped from 0.600 M to 0.512 M. Calculate the average rate of the reaction during this time interval.
Problem 25c
Consider the reaction:
2 HBr (g) → H2 (g) + Br2 (g)
c. If the volume of the reaction vessel in part b was 1.50 L, what amount of Br2 (in moles) was formed during the first 15.0 s of the reaction?
- Consider the reaction: 2 N2O(g) → 2 N2(g) + O2(g). In the first 15.0 s of the reaction, 0.015 mol of O2 is produced in a reaction vessel with a volume of 0.500 L. a. What is the average rate of the reaction during this time interval? b. Predict the rate of change in the concentration of N2O during this time interval, i.e., what is ∆[N2O]/∆t?
Problem 26
Problem 26a
Consider the reaction: 2 N2O( g) → 2 N2(g) + O2(g) a. Express the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Problem 27a
For the reaction 2 A(g) + B(g) → 3 C(g), a. Determine the expression for the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Problem 27b
For the reaction 2 A(g) + B(g) → 3 C(g), b. when A is decreasing at a rate of 0.100 M/s, how fast is B decreasing? How fast is C increasing?
- For the reaction A(g) + 1/2 B(g) → 2 C(g): b. When C is increasing at a rate of 0.025 M/s, how fast is B decreasing? How fast is A decreasing? a. Determine the expression for the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Problem 28
- Is this the correct formulation for the task of completing the table for the reaction: Cl2(g) + 3 F2(g) → 2 ClF3(g)?
Problem 29
Problem 30
Consider the reaction: 8 H2S(g) + 4 O2(g) → 8 H2O(g) + S8(g) Complete the table.
- What is the rate of formation of C2H4 between 20 and 30 seconds for the reaction: C4H8(g) → 2 C2H4(g), given the tabulated data collected for the concentration of C4H8 as a function of time?
Problem 31
Problem 31a
Consider the reaction: C4H8( g) → 2 C2H4( g) The tabulated data were collected for the concentration of C2H4 as a function of time: a. What is the average rate of the reaction between 0 and 10 s? Between 40 and 50 s?
Problem 32a
Consider the reaction: NO2(g) → NO(g) + 1/2 O2(g) The tabulated data were collected for the concentration of NO2 as a function of time: a. What is the average rate of the reaction between 10 and 20 s? Between 50 and 60 s?
Problem 32b
Consider the reaction: NO2(g) → NO(g) + 1/2 O2( g) The tabulated data were collected for the concentration of NO2 as a function of time: b. What is the rate of formation of O2 between 50 and 60 s?
- Consider the reaction: H2(g) + Br2(g) → 2 HBr(g). The graph shows the concentration of Br2 as a function of time. a. Use the graph to calculate each quantity: (ii) the instantaneous rate of the reaction at 25 s.
Problem 33
Problem 33ai
Consider the reaction: H2(g) + Br2(g) → 2 HBr(g) The graph shows the concentration of Br2 as a function of time.
a. Use the graph to calculate each quantity: (i) the average rate of the reaction between 0 and 25 s
Problem 33aiii
Consider the reaction: H2(g) + Br2(g) → 2 HBr(g) The graph shows the concentration of Br2 as a function of time. a. Use the graph to calculate each quantity: (iii) the instantaneous rate of formation of HBr at 50 s
Problem 33b
Consider the reaction: H2( g) + Br2( g) → 2 HBr( g) The graph shows the concentration of Br2 as a function of time.
b. 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
- Consider the 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 each quantity: a. the average rate of the reaction between 10 and 20 seconds, b. the instantaneous rate of the reaction at 30 seconds.
Problem 34
Problem 34c
Consider the 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 each quantity: c. the instantaneous rate of formation of O2 at 50 s
Problem 34d
Consider the 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 each quantity: d. If the initial volume of the H2O2 is 1.5 L, what total amount of O2 (in moles) is formed in the first 50 s of reaction?
Problem 35a
This graph shows a plot of the rate of a reaction versus the concentration of the reactant A for the reaction A → products. a. What is the order of the reaction with respect to A?
Problem 35c
This graph shows a plot of the rate of a reaction versus the concentration of the reactant A for the reaction A → products. c. Write a rate law for the reaction including an estimate for the value of k.
