Question

For the reaction

cyclopropane → propene
a plot of In[cyclopropane] vs time in seconds gives a straight line with slope -4.1x103 s at 550 °C. What is the rate constant for this reaction?
A) 3.9 x 10⁻² s⁻¹
B) 8.2 x 10⁻³ s⁻¹
C) 4.1 x 10⁻³ s⁻¹
D) 1.8 x 10⁻³ s⁻¹
E) 2.1 x 10⁻³ s⁻¹

Answer 1

The rate constant for the first-order reaction of cyclopropane to propene at 550 °C is 4.1 x 10³ s¹, as indicated by the slope of the ln[cyclopropane] versus time plot.

Step-by-step explanation:

The rate constant for the reaction is given by the slope of the plot of ln[cyclopropane] versus time. In this case, the slope is -4.1 x 10³ s⁻¹. The rate constant can be calculated by dividing the slope by the temperature:

rate constant = -4.1 x 10³ s⁻¹ / 550 K

After performing the calculation, the rate constant is found to be approximately 7.45 x 10⁻³ s⁻¹. Therefore, the correct answer is B) 8.2 x 10⁻³ s⁻¹.