For the gas phase decomposition of bromoethane , the rate constant in s -1 has b
ID: 814818 • Letter: F
Question
For the gas phase decomposition of bromoethane,
the rate constant in s-1 has been determined at several temperatures. When ln k is plotted against the reciprocal of the Kelvin temperature, the resulting linear plot has a slope of -2.63E4 K and a y-intercept of 29.6.
The value of the rate constant for the gas phase decomposition of bromoethane at 721 K is ______ s-1.
(Enter your answer to one significant figure.)
For the gas phase decomposition of bromoethane,
the rate constant has been determined at several temperatures. When ln k in s-1 is plotted against the reciprocal of the Kelvin temperature, the resulting linear plot has a slope of -2.63E4 K and a y-intercept of 29.6.
The activation energy for the gas phase decomposition of bromoethane is ________kJ/mol.
Explanation / Answer
In the plot of lnk vs 1/T the slope = E/2.303R= -2.63 *104 and intercept = A= 29.6
-E/2.303R=-2.63 *104
E= 2.63 *104 * 2.303 * 8.314 JK-1mol-1 = 50.36 *104 J/ mol
According to Arrhenius equation
k = A e-E/RT
= 29.6 e -(50.36 * J/8.314 JK-1mol-1* 721) = 29.35~ 3 sec-1
---------------------------------------------------------------------------------------------------------------------------
-Eact / RT = -2.63 *104
E= 2.63 *104 * 2.303 * 8.314 JK-1mol-1 = 50.36 *104 J/ mol = 0.050 kJ/mol