Chemistry of the Environment The first-order rate constant for the decomposition of a certain insecticide in water at 12°C is 1.45 yr¹. A quantity of this insecticide is washed into a lake on April 13, leading to a concentration of 5.0 ppb (parts per billion) of water. Assume that the effective temperature of the lake is 12°C and density of lake water = 1g/cm³. 1. What is the concentration of the insecticide on April 13 of the following year? 2. How long will it take for the concentration of insecticide to drop to 3.0 x10 "g/L?

The rate constant of a certain reaction is known to obey the Arrhenius equation, and to have an activation energy Ea=19.0/kJmol. If the rate constant of this reaction is 2.3 x 106·M−1s−1 at 332.0°C, what will the rate constant be at 302°C? Round your answer to 2 significant digits.

Be sure to answer all parts. The second-order rate constant for the decomposition of nitrous oxide to nitrogen molecules and oxygen atoms has been determined at various temperatures: Determine the activation energy graphically.  k(M−1  ·  s−1) T( ° C) 1.87  ×  10−3 600 0.0113 650 0.0569 700 0.244 750

Dinitrogen pentoxide decomposes in the gas phase to form nitrogen dioxide and oxygen gas. The reaction is first order in dinitrogen pentoxide and has a half-life of 2.72 h at 25 °C. Part A If a 1.8 L reaction vessel initially contains 770 Torr of N2O5 at 25 °C, what partial pressure of O2 will be present in the vessel after 205 minutes? Express your answer in torr as an integer. P = VG ΑΣΦ ? Torr

The rate constants for the decomposition of dinitrogen pentoxide are3.7x10-5 s-1 at 25 oC and 1.7x10-3 s-1 at 55 oC.2 N2O5 (g) → 4 NO2 (g) + O2 (g) -Determine the activation energy for this reaction in KJ/mol.

Your laboratory is asked to analyze a water sample for a particular pesticide. You know from previous study that this pesticide degrades via a first order, irreversible reaction. The first order rate constant (k) for the reaction at 4 °C is 0.02 day¹. The activation energy for the reaction is known to be 10 kcal/mol. The standard preservation method for water samples containing this pesticide is to store the sample at 4 °C for no more than 24 hours prior to analysis. Calculate the fraction of the pesticide that remains in the sample after 24 hours of storage at 4 °C. b. A newly hired staff member collects a sample of the water but forgets to store it at 4 °C. Instead, they leave the sample in the trunk of their car (average temperature 35 °C) over the weekend. 60 hours later the sample is analyzed and found to contain 0.01 mg/L of the pesticide. What was the pesticide concentration in the water at the time the sample was taken?

Under certain conditions the rate of this reaction is zero order in dinitrogen monoxide with a rate constant of 0.0086 M's : 2 N,0 (g) → 2 N2 (g) + 0, (g) Suppose a 300. mL flask is charged under these conditions with 100. mmol of dinitrogen monoxide. How much is left 10. s later? You may assume no other reaction is important. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits. x10 미