Kinetic studies of fluroalkanes with tropospheric oxidants

The reactions of fluoroalkanes with tropospheric oxidants, OH radical and Cl atom, are studied to measure the rate coefficients, and to understand their degradation pathways. The measured rate coefficients for reactions of fluoropentane and fluoroheptane with OH were found to be as (3.4 ± 0.5) and (4.5 ± 0.4)×10^-12 cm³ molecule^-1 s^-1, respectively and that with Cl atom were found to be (1.9 ± 0.4) and (9.6 ± 0.8) ×10^-10 cm³ molecule^-1 s^-1, respectively. These rate coefficients have been used to calculate tropospheric lifetimes (τ), which are found to be >10 hours for both the molecules, indicating atmospheric impact of these molecules to be regional. (author)