Answer:
2.1 × 10⁻¹⁹ M/s
Explanation:
Let's consider the degradation of CF₃CH₂F by OH radicals.
CF₃CH₂F + OH → CF₃CHF + H₂O
Considering the order of reaction for each reactant is 1 and the rate constant is 1.6 × 10⁸ M⁻¹s⁻¹, the rate law is:
r = 1.6 × 10⁸ M⁻¹s⁻¹.[CF₃CH₂F].[OH]
where,
r is the rate of the reaction
If the tropospheric concentrations of OH and CF₃CH₂F are 8.1 × 10⁵ and 6.3 × 10⁸ molecules/cm³, respectively, what is the rate of reaction at this temperature in M/s?
The Avogadro's number is 6.02 × 10²³ molecules/mole.
The molar concentration of OH is:
[tex]\frac{8.1 \times 10^{5}molecules}{cm^{3}}.\frac{1mol}{6.02 \times 10^{23}molecules }.\frac{1000cm^{3} }{1L} =1.3 \times 10^{-15} M[/tex]
The molar concentration of CF₃CH₂F is:
[tex]\frac{6.3 \times 10^{8}molecules}{cm^{3}}.\frac{1mol}{6.02 \times 10^{23}molecules }.\frac{1000cm^{3} }{1L} =1.0 \times 10^{-12} M[/tex]
r = 1.6 × 10⁸ M⁻¹s⁻¹ × 1.0 × 10⁻¹² M × 1.3 × 10⁻¹⁵ M = 2.1 × 10⁻¹⁹ M/s
