What is the rate for the first order reaction A → Products when [A] = 0.276 M? (k = 0.360 1/min)

For a first order gas phase reaction A products, k = 7.2 104s1 at 660. K and k = 1.7 102s1 at 720. K. If the initial pressure of A is 536 torr at 295C, how long will it take for the pressure of A to decrease to 268 torr?

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?

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?

Ammonium cyanate, NH4NCO, rearranges in water to give urea, (NH2)2CO. NH4NCO(aq) (NH2)2CO(aq) Using the data in the table: (a) Decide whether the reaction is first-order or second-order. (b) Calculate k for this reaction. (c) Calculate the half-life of ammonium cyanate under these conditions. (d) Calculate the concentration of NH4NCO after 12.0 hours.

One experimental procedure that can be used to determine the rate law of a reaction is the method of initial rates. What data are gathered in the method of initial rates, and how are these data manipulated to determine k and the orders of the species in the rate law? Are the units for k. the rate constant, the same for all rate laws? Explain. If a reaction is first order in A, what happens to the rate if [A] is tripled? If the initial rate for a reaction increases by a factor of 16 when [A] is quadrupled, what is the order of n? If a reaction is third order in A and [A] is doubled, what happens to the initial rate? If a reaction is zero order, what effect does [A] have on the initial rate of a reaction?

The reaction H2SeO3(aq) + 6I-(aq) + 4H+(aq) Se(s) + 2I-3(aq) + 3H2O(l) was studied at 0C, and the following data were obtained: [H2SeO3]0 (mol/L) [H+]0 (mol/L) [I]0(mol/L) Initial Rate (mol/L s) 1.0 104 2.0 102 2.0 102 1.66 107 2.0 104 2.0 102 2.0 10-2 3.33 107 3.0 104 2.0 102 2.0 102 4.99 107 1.0 104 4.0 102 2.0 102 6.66 107 1.0 104 1.0 102 2.0 102 0.42 107 1.0 104 2.0 102 4.0 102 13.2 107 1.0 104 1.0 102 4.0 102 3.36 107 These relationships hold only if there is a very small amount of I3 present. What is the rate law and the value of the rate constant? (Assumethatrate=[H2SeO3]t)

In the presence of excess thiocyanate ion, SCN, the following reaction is first order in iron(III) ion, Fe3+; the rate constant is 1.27/s. Fe3+(aq)+SCN(aq)Fe(SCN)2+(aq) What is the half-life in seconds? How many seconds would be required for the initial concentration of Fe3+ to decrease to each of the following values: 25.0% left, 12.5% left, 6.25% left, 3.125% left? What is the relationship between these times and the half-life?

The following statements relate to the reaction for the formation of HI: H2(g) + I2(g) -* 2 HI(g) Rate = it[HJ [I2J Determine which of the following statements are true. If a statement is false, indicate why it is incorrect. The reaction must occur in a single step. This is a second-order reaction overall. Raising the temperature will cause the value of k to decrease. Raising the temperature lowers the activation energy' for this reaction. If the concentrations of both reactants are doubled, the rate will double. Adding a catalyst in the reaction will cause the initial rate to increase.

The decomposition of sulfuryl chlorideSO2Cl2fur dioxide and chlorine gases is a first-order reaction. It is found that at a certain temperature, it takes 1.43 hours to decompose 0.0714 M to 0.0681 M. (a) What is the rate constant for the decomposition? (b) What is the rate of decompostion [ SO2Cl2 ]=0.0462M? (c) How long will it take to decompose SO2Cl2 so that 45% remains?