The influence of temperature on the specific reaction rate is very large in that, at ordinary temperatures, the rate increases by 10 to 15 per cent for each one-degree rise in temperature. It cannot be assumed, therefore, that the increasing reaction velocity comes from the increasing frequency of collisions of the reacting molecules. According to the kinetic theory of gases, the velocity of the gas molecules changes only by about 1/6 per cent of its value for each one-degree rise in temperature and the frequency of collisions increases in the same ratio.1) Use a formula for a typical molecular speed (average speed, root mean square speed, or most likely speed) to compute the percentage increase in speed for the following one-degree temperature increases:
2) Using the equation we now call the Arrhenius equation for a reaction rate constant, compute the activation energy for a reaction if its rate constant increases
a) 10%
b) 15%
when the temperature is raised from 25°C to 26°C.
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