Calculate the fraction of atoms in a sample of argon gas at 400 K that have an energy of 10.0 kJ or greater.
1 answer:
Answer:
The answer to this can be arrived at by clculating the mole fraction of atoms higher than the activation energy of 10.0 kJ by pluging in the values given into the Arrhenius equation. The answer to this is 20.22 moles of Argon have energy equal to or greater than 10.0 kJ
Explanation:
From Arrhenius equation showing the temperature dependence of reaction rates.
where
k = rate constant
A = Frequency or pre-exponential factor
Ea = energy of activation
R = The universal gas constant
T = Kelvin absolute temperature
we have
Where
f = fraction of collision with energy higher than the activation energy
Ea = activation energy = 10.0kJ = 10000J
R = universal gas constant = 8.31 J/mol.K
T = Absolute temperature in Kelvin = 400K
In the Arrhenius equation k = Ae^(-Ea/RT), the factor A is the frequency factor and the component e^(-Ea/RT) is the portion of possible collisions with high enough energy for a reaction to occur at the a specified temperature
Plugging in the values into the equation relating f to activation energy we get
or f =
= 20.22 moles of argon have an energy of 10.0 kJ or greater
You might be interested in
Answer:
Kinetic energy is directly proportional to mass
Explanation:
Kinetic energy is directly proportional to the mass of an object and also directly proportional to the square of the velocity of that object:
Notice that if we keep velocity constant and only increase the mass of a object, the kinetic energy of that object would increase, as we've already emphasized the direct relationship between the kinetic energy term and the mass term.
Let's take a simple example: assume that object 1 and object 2 are both moving at the same velocity but object 1 has a much lower mass than object 2. According to the equation, object 1 has lower kinetic energy. This object can then transform all of its kinetic energy into some other form, say, heat the ground. The heat transferred will be significantly lower than by the object 2 moving at the same velocity but having a much greater mass.