In a Breathalyzer test, the reaction to determine the alcohol level is: 2K2Cr2O7 + 8H2SO4 + 3C2H6O2Cr2(SO4)3 + 2K2SO4 + 2C2H4O2 +11H20 If the rate of appearance of Cr2(SO4)3 is 1.24 mol/min, what is the rate of disappearance of C2H6O? a) 1.21 mol/min b) 2.13 mol/min c) 3.46 mol/min d) 0.94 mol/min e1.86 mol/min f) 0.38 mol/min

In a Breathalyzer test, the reaction to determine the alcohol level is: 2K2Cr2O7 + 8H2SO4 + 3C2H6O2Cr2(SO4)3 + 2K2SO4 + 2C2H4O2 +11H20 If the rate of appearance of Cr2(SO4)3 is 1.24 mol/min, what is the rate of disappearance of C2H6O? a) 1.21 mol/min b) 2.13 mol/min c) 3.46 mol/min d) 0.94 mol/min e1.86 mol/min f) 0.38 mol/min

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter11: Rate Of Reaction

Section: Chapter Questions

Problem 39QAP: The decomposition of azomethane, (CH3)2N2, to nitrogen and ethane gases is a first-order reaction,...

See similar textbooks

Similar questions

The label on a bottle of 3% (by volume) hydrogen peroxide, H2O2, purchased at a grocery store, states that the solution should be stored in a cool, dark place. H2O2decomposes slowly over time, and the rate of decomposition increases with an increase in temperature and in the presence of light. However, the rate of decomposition increases dramatically if a small amount of powdered MnO- is added to the solution. The decomposition products are H2O and O2. MnO2 is not consumed in the reaction. Write the equation for the decomposition of H2O2. What role does MnO2 play? In the chemistry lab, a student substituted a chunk of MnO2 for the powdered compound. The reaction rate was not appreciably increased. WTiat is one possible explanation for this observation? Is MnO2 part of the stoichiometry of the decomposition of H2O2?
At 620. K butadiene dimerizes at a moderate rate. The following data were obtained in an experiment involving this reaction: t(s) [C4H6] (mol/L) 0 0.01000 1000.. 0.00629 2000. 0.00459 3000. 0.00361 a. Determine the order of the reaction in butadiene. b. In how many seconds is the dimerization 1.0% complete? c. In how many seconds is the dimerization 10.0% complete? d. What is the half-life for the reaction if the initial concentration of butadiene is 0.0200 M? e. Use the results from this problem and Exercise 45 to calculate the activation energy for the dimerization of butadiene.
11.64 HBr is oxidized in the following reaction: 4 HBr(g) + O2(g) —• 2 H2O(g) + 2 Br,(g) A proposed mechanism is HBr + O2 -* HOOBr (slow) HOOBr + HBr — 2 HOBr (fast) HOBr + HBr — H2O + Bn (fast) Show that this mechanism can account for the correct stoichiometry. Identify all intermediates in this mechanism. What is the molecularity of each elementary’ step? Write the rate expression for each elementary' step. Identify the rate-determining step.
Gaseous azomethane (CH3N2CH3) decomposes to ethane and nitrogen when heated: CH3N2CH3(g) CH3CH3(g) + N2(g) The decomposition of azomethane is a first-order reaction with k = 3.6 104 s1 at 600 K. (a) A sample of gaseous CH3N2CH3 is placed in a flask and heated at 600 K for 150 seconds. What fraction of the initial sample remains after this time? (b) How long must a sample be heated so that 99% of the sample has decomposed?
The decomposition of azomethane, (CH3)2N2, to nitrogen and ethane gases is a first-order reaction, (CH3)2N2(g)N2(g)+C2H6(g). At a certain temperature, a 29-mg sample of azomethane is reduced to 12 mg in 1.4 s. (a) What is the rate constant k for the decomposition at that temperature? (b) What is the half-life of the decomposition? (c) How long will it take to decompose 78% of the azomethane?
Phenyl acetate, an ester, reacts with water according to the equation The data in the table were collected for this reaction at 5 C. (a) Plot the phenyl acetate concentration versus time, and describe the shape of the curve observed. (b) Calculate the rate of change of the phenyl acetate concentration during the period 15.0 seconds to 30.0 seconds and also during the period 75.0 seconds to 90.0 seconds. Why is one value smaller than the other?
The plot below shows the number of collisions with a particular energy for two different temperatures. a. Which is greater, T2 or T1? How can you tell? b. What does this plot tell us about the temperature of the rate of a chemical reaction? Explain your answer.
The initial concentration of the reactant in a tirst-order reaction A —» products is 0.64 rnol/L and the half-life is 30.0 s. Calculate the concentration of the reactant exactly 60 s after initiation of the reaction. How long would it take for the concentration of the reactant to drop to one-eighth its initial value? How long would it take for the concentration of the reactant to drop to 0.040 mol/L?
6. Phenyl acetate, an ester, reacts with water according to the equation The data in the table were collected for this reaction at 5°C. Time (s) [Phenyl acetate] (mol/L) 0 0.55 15.0 0.42 30.0 0.31 45.0 0.23 60.0 0.17 75.0 0.12 90.0 0.085 Plot the phenyl acetate concentration versus time, and describe the shape of the curve observed. Calculate the rate of change of the phenyl acetate concentration during the period 15.0 seconds to 30.0 seconds and also during the period 75.0 seconds to 90.0 seconds. Why is one value smaller than the other? What is the rate of change of the phenyl acetate concentration during the time period 60.0 seconds to 75.0 seconds? What is the instantaneous rate at 15.0 seconds?
As with any drug, aspirin (acetylsalicylic acid) must remain in the bloodstream long enough to be effective. Assume that the removal of aspirin from the bloodstream into the urine is a lirst-order reaction, with a half-life of about 3 hours. The instructions on an aspirin bottle say to take 1 or 2 tablets every 4 hours. If a person takes 2 aspirin tablets, how much aspirin remains in the bloodstream when it is time for the second dose? (A standard tablet contains 325 mg of aspirin.)