Your laboratory is asked to analyze a water sample for a particular pesticide. You knowfrom previous study that this pesticide degrades via a first order, irreversible reaction. Thefirst order rate constant (k) for the reaction at 4 °C is 0.02 day¹. The activation energy forthe reaction is known to be 10 kcal/mol. The standard preservation method for watersamples containing this pesticide is to store the sample at 4 °C for no more than 24 hoursprior to analysis.Calculate the fraction of the pesticide that remains in the sample after 24 hours of storageat 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) overthe weekend. 60 hours later the sample is analyzed and found to contain 0.01 mg/L ofthe pesticide. What was the pesticide concentration in the water at the time the samplewas taken?

a) Here initial concentration (t=0) of pesticide is a0. After time 24 hrs (t1) the concentration of…

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 day. 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. a. 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?

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 day. 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. a. 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?

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter11: Chemical Kinetics: Rates Of Reactions

Section: Chapter Questions

Problem 11.ACP: (Section 11-5) A rule of thumb is that for a typical reaction, if concentrations are unchanged, a...

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