Welcome to Westonci.ca, where curiosity meets expertise. Ask any question and receive fast, accurate answers from our knowledgeable community. Connect with professionals ready to provide precise answers to your questions on our comprehensive Q&A platform. Get detailed and accurate answers to your questions from a dedicated community of experts on our Q&A platform.

A particular first-order reaction has a rate constant of 1.35 × 10^2 s−1 at 25.0 ∘C. What is the magnitude of k at 65.0∘C if Ea = 55.5 kJ/mol.

Sagot :

The magnitude of k at 65.0∘C : 1912.7 /s

Further explanation

Given

k at 25 °C = 1.35 x 10² /s k1

T₁=25 + 273 = 298 K

T₂=65 + 273 = 338 K

Required

the magnitude of k at 65.0∘C

Solution

Arrhenius Equation :

[tex]\tt ln(\dfrac{k_1}{k_2})=(\dfrac{1}{T_2}-\dfrac{1}{T_1})\dfrac{Ea}{R}[/tex]

R : gas constant= 8.314 J/molK

Input the value :

[tex]\tt ln(\dfrac{1.35\times 10^2}{k_2})=(\dfrac{1}{338}-\dfrac{1}{298})\dfrac{55.5.10^3}{8.314}\\\\ln(\dfrac{135}{k_2})=-2.651\rightarrow \dfrac{135}{k_2}=e^{-2.651}\rightarrow k_2=1912.7[/tex]

The magnitude of k will be "1912.7".

Temperature,

  • [tex]T_1 = 25^{\circ} C[/tex] or, [tex]298 \ K[/tex]
  • [tex]T_2 = 65^{\circ} C[/tex] or, [tex]338 \ K[/tex]

Rate constant,

  • [tex]1.35\times 10^2 \ s^{-1}[/tex]

Gas constant,

  • [tex]R = 8.314 \ J/mol[/tex]

By using the Arrhenius equation, we get

→ [tex]ln (\frac{k_1}{k_2} ) = (\frac{1}{T_2} - \frac{1}{T_1} )\frac{Ea}{R}[/tex]

By substituting the values, we get

→ [tex]ln (\frac{1.35\times 10^2}{k_2} ) = (\frac{1}{338} - \frac{1}{298} )\frac{55.5\times 10^3}{8.314}[/tex]

→        [tex]ln (\frac{135}{k_2} ) = -2.651[/tex]

                [tex]\frac{135}{k_2} = e^{-2.651}[/tex]

                 [tex]k_2 = 1912.7[/tex]

Thus the response above is right.

Learn more about magnitude here:

https://brainly.com/question/8964080