The gas phase reaction 2 N2O5(g) → 4 NO2(g) + O2(g) has an activation energy of 103 kJ/mol, and the first order rate constant is 1.35×10-5 min-1 at 266 K. What is the rate constant at 296 K?

Respuesta :

Answer:  The rate constant at 296 K is [tex]1.51\times 10^{-3}min^{-1}[/tex]

Explanation:

According to the Arrhenius equation,

[tex]K=A\times e^{\frac{-Ea}{RT}}[/tex]

or,

[tex]\log (\frac{K_2}{K_1})=\frac{Ea}{2.303\times R}[\frac{1}{T_1}-\frac{1}{T_2}][/tex]

where,

[tex]K_1[/tex] = rate constant at 266 K = [tex]1.35\times 10^{-5}min^{-1}[/tex]

[tex]K_2[/tex] = rate constant at 296 K = ?

[tex]Ea[/tex] = activation energy for the reaction = 103 kJ/mol = 103000 J/mol

R = gas constant = 8.314 J/mole.K

[tex]T_1[/tex] = initial temperature = 266 K

[tex]T_2[/tex] = final temperature = 296 K

Now put all the given values in this formula, we get

[tex]\log (\frac{K_2}{1.35\times 10^{-5}})=\frac{103000}{2.303\times 8.314J/mole.K}[\frac{1}{266}-\frac{1}{296}][/tex]

[tex]\log (\frac{K_2}{1.35\times 10^{-5}})=2.049[/tex]

[tex]K_2=1.51\times 10^{-3}min^{-1}[/tex]

Thus the rate constant at 296 K is [tex]1.51\times 10^{-3}min^{-1}[/tex]