Question

What is the slope of an Arrhenius plot for the following reaction? 2NOCl → 2NO + Cl 2 Picture

a. 8.18 × 10−2 K
b. 5.06 × 10−2 K
c. −1.22 × 104 K
d. −1.96 × 104 K
e. not enough information to calculate the slope

Answer 1

Answer:

c. −1.22 × 10^4 K

Explanation:

Generally, the slope of an Arrhenius plot can be determined either from the graph of In k against 1/T or the available experimental data of the rate constant (k) and the absolute temperature. Mathematically,

$slope = \frac{ln k_{2} -ln k_{1} }{\frac{1}{T_{2} }-\frac{1}{T_{1} }   }$

Where:

$k_{1} = 6.6*10^-4$ L/(mol.s)

$k_{2} = 2.9*10^-1$ L/(mol.s)

$T_{1} = 400$ K

$T_{2} = 500$ K

slope = (ln 2.9*10^-1 - ln 6.6*10^-4)/(1/500 - 1/400)

slope = (-1.238+7.323)/(0.002-0.0025)

slope = 6.085/-0.0005 = -1.22*10^4 K