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Find the temperature at which the concentration is maximum

ML_10228582
2-Guest

Find the temperature at which the concentration is maximum

Hello! I'm new to MathCad and I'm having trouble solving a kinetics and reactor calculus problem.

I have to find the temperature at which the concentration of B reaches its maximum value. I did this by manually guessing values, but I was wondering if it's possible to do it in an easier way.
The constants k depend on the temperature. The concentration of A depends on the constants k. And finally, the concentration of B depends on the constants k and the concentration of A. The temperature I found was 306K. Would it be possible to synthesize all these calculations in a solve block? The following is the resolution and the way I was trying.

 

problem.png

 

problm2.png

1 ACCEPTED SOLUTION

Accepted Solutions

4 REPLIES 4

Please attach your Prime sheet. Its way harder to debug a pic than a live worksheet.

I see no "B" nor any equation for the concentration of B in your pics.

Furthermore its irritation that your various k and A values are of different dimensions (units)

 

And then: Whats the reason for using a solve block to calculate the three C-values? It looks like you can define them directly via assignments.

 

> The concentration of A depends on the constants k. 

It looks like its the other way round. In your pics you first define A's (different units!?) and then k dependent on a (and temp).

 

As I see it you will have to make k.1,2,3 functions of T and also turn the solve block for C.A into a function of T.
Then you can turn C.B into a function of T and find its maximum.
Similar to what you tried in your second pic but it looks like here the calculation of C.A is missing.

 

It's question f), ignore the other questions.
To find the concentration of B you would need to find the constant k2 and the concentration of A (Ca), the formula (τ*k2*Ca), whose variables depend on temperature. The parameters A are the pre-exponential factors of the Arrhenius equation, they have different units because the constants k also have different units (different order reactions). I would like to know a way to synthesize all these calculations. I don't know how to use the maximize function.
Anyway, thanks for the help!

Here you are:

Werner_E_1-1646417237418.png

 

Thanksss!!

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