Chemistry- two point Arrhenius Equation (miscalculation?)

In summary, the value of the rate constant at 75 degrees celsius can be calculated using the Arrhenius Equation with the given values of T1, T2, K1, and Ea. After plugging in the values and solving, the resulting value for K2 is 4.8 x 10^3 s^-1. However, there is some uncertainty whether this is the correct solution.
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Chemistry- two point Arrhenius Equation (miscalculation??)

Homework Statement



At 25 degrees celsius, the first-order rate constant for a reaction is 2.0 x 10^3 s^-1. The activation energy is 15.0 kJ/mol. what is the value of the rate constant at 75 degrees celsius.

T1= 298.15 K
T2= 348.15 K
K1= 2.0 x 10^3 s^-1
Ea= 15.0 kJ/mol
K2= ??


Homework Equations



K2=K1(e^[(Ea/R)(1/T1-1/T2)])


The Attempt at a Solution



K2= 2.0 x 10^3 s^-1(e^[(15.0 kJ/mol / 8.3145 J/molK)(10^3 J / 1 kJ)(0.0036 K - 0.0029 K)])

I can't remember if the solution is supposed to be 4.8 x 10^3 s^-1. This is taken from my notes that I have on my course guide. I am basically trying to replicate the entire process, but I keep coming up with over sized answers that are to the 9th power or something... -.-
 
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lol i can't understand your work...try using the super and subscripts and latex...then maybe people can read what you're trying to say
 
  • #3




The solution for the rate constant at 75 degrees celsius (K2) should be 4.8 x 10^3 s^-1. However, your calculation may have been incorrect due to a miscalculation in the Arrhenius equation. It is important to double-check your calculations and ensure that all units are consistent. Additionally, it may be helpful to use scientific notation to avoid large numbers and potential errors. If you are still getting significantly different values, it may be worth consulting with your instructor or a peer for further clarification and assistance.
 

1. What is the Arrhenius Equation in chemistry and how is it used?

The Arrhenius Equation is a mathematical formula used to explain the relationship between temperature and the rate of a chemical reaction. It is often used to calculate the activation energy of a reaction and predict how changing the temperature will affect the reaction rate.

2. What is a common mistake when using the Arrhenius Equation?

A common mistake when using the Arrhenius Equation is miscalculating the activation energy (Ea) or the pre-exponential factor (A). These values need to be accurate in order for the equation to provide accurate predictions.

3. Can small errors in the Arrhenius Equation lead to significant changes in the predicted reaction rate?

Yes, even small errors in the values used in the Arrhenius Equation can lead to significant changes in the predicted reaction rate. This is because the equation involves exponential terms, so even a small change in these values can result in a large change in the final result.

4. How can I minimize errors when using the Arrhenius Equation?

To minimize errors when using the Arrhenius Equation, it is important to use accurate and precise values for the activation energy and pre-exponential factor. These values can be determined experimentally or by using reliable sources. It is also important to ensure that the units for temperature are consistent throughout the equation.

5. Are there any limitations to the Arrhenius Equation?

Yes, the Arrhenius Equation has certain limitations. It assumes that the reaction is a simple, one-step process and does not take into account any intermediate steps. It also assumes that the temperature is the only factor affecting the reaction rate, when in reality, other factors such as concentration and catalysts can also play a role.

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