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Done the arrhenius equation wrong?

Okay so i kept my concentrations of reactants constant and then i did...
one exp at 45 degrees, where i warmed the solutions up to 45 degrees mixed them and then placed a sample of the solution in the colorimeter so i could monitor the absorbance over time then the same at 30, 20 and 10 degrees
Then drew a tangent to each curve at the time t=0 and calculated the inital rate of reaction which im gonna use later on.
Just wondering tho cos your ment to keep the temperature constant or is heating them and then removing them from the heat and monitoring the reaction okay?
Original post by misfit1993
Okay so i kept my concentrations of reactants constant and then i did...
one exp at 45 degrees, where i warmed the solutions up to 45 degrees mixed them and then placed a sample of the solution in the colorimeter so i could monitor the absorbance over time then the same at 30, 20 and 10 degrees
Then drew a tangent to each curve at the time t=0 and calculated the inital rate of reaction which im gonna use later on.
Just wondering tho cos your ment to keep the temperature constant or is heating them and then removing them from the heat and monitoring the reaction okay?


As soon as you remove them from the heat source they will start to cool down. This introduces inaccuracy into the experimental design.

Make sure that you discuss this in the evaluation. It does not invalidate the experiment, but it does lead to inaccuracy.
Reply 2
Original post by charco
As soon as you remove them from the heat source they will start to cool down. This introduces inaccuracy into the experimental design.

Make sure that you discuss this in the evaluation. It does not invalidate the experiment, but it does lead to inaccuracy.


Thankyou, when doing the arrhenius equation do you plott ln(rate constant) against 1/t or ln(rate)?
Original post by misfit1993
Thankyou, when doing the arrhenius equation do you plott ln(rate constant) against 1/t or ln(rate)?


1/t

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