1. Consider the thermal decomposition of gaseous N₂Os to NO2 and O₂ via the following equation: 2N2Os(g) 4NO2(g)+O2(g) Write expressions for the reaction rate in terms of the rates of change in the concentrations of the reactant and each product with time. Given reaction 2 N₂Os(g) 4 NO2(g) + O2(g))

The reaction NO(g) + O,(g) — NO,(g) + 0(g) plays a role in the formation of nitrogen dioxide in automobile engines. Suppose that a series of experiments measured the rate of this reaction at 500 K and produced the following data; [NO] (mol L ’) [OJ (mol L 1) Rate = -A[NO]/Af (mol L_1 s-1) 0.002 0.005 8.0 X 10"'7 0.002 0.010 1.6 X 10-'6 0.006 0.005 2.4 X IO-'6 Derive a rate law for the reaction and determine the value of the rate constant.

Nitryl fluoride is an explosive compound that can be made by oxidizing nitrogen dioxide with fluorine: 2 NO2(g) + F2(g) → 2 NO2F(g) Several kinetics experiments, all done at the same temperature and involving formation of nitryl fluoride, are summarized in this table: Write the rate law for the reaction. Determine what the order of the reaction is with respect to each reactant and each product. Calculate the rate constant k and express it in appropriate units.

The decomposition of ozone is a second-order reaction with a rate constant of 30.6 atm1 s1 at 95 C. 2O3(g)3O2(g) If ozone is originally present at a partial pressure of 21 torr, calculate the length of time needed for the ozone pressure to decrease to 1.0 torr.

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?

The decomposition of iodoethane in the gas phase proceeds according to the following equation: C2H5I(g)C2H4(g)+HI(g) At 660. K, k = 7.2 104 sl; at 720. K, k = 1.7 102 sl. What is the value of the rate constant for this first-order decomposition at 325C? If the initial pressure of iodoethane is 894 torr at 245C, what is the pressure of iodoethane after three half-lives?

At 573 K, gaseous NO2(g) decomposes, forming NO(g) and O2(g). If a vessel containing NO2(g) has an initial concentration of 1.9 102 mol/L, how long will it take for 75% of the NO2(g) to decompose? The decomposition of NO2(g) is second-order in the reactant and the rate constant for this reaction, at 573 K, is 1.1 L/mol s.

Can a reaction mechanism ever be proven correct? Can it be proven incorrect?

For a reaction involving the decomposition of Z at a certain temperature, the following data are obtained: (a) What is the order of the reaction? (b) Write the rate expression for the decomposition of Z. (c) Calculate k for the decomposition at that temperature.

Some bacteria are resistant to the antibiotic penicillin because they produce penicillinase, an enzyme with a molecular weight of 3104 g/mol that converts penicillin into inactive molecules. Although the kinetics of enzyme-catalyzed reactions can be complex, at low concentrations this reaction can be described by a rate equation that is first order in the catalyst (penicillinase) and that also involves the concentration of penicillin. From the following data: 1.0 L of a solution containing 0.15 g ( 0.15106 g) of penicillinase, determine the order of the reaction with respect to penicillin and the value of the rate constant. [Penicillin] (M) Rate (mol/L/min) 2.0106 1.01010 3.0106 1.51010 4.0106 2.01010