[Altered State]

I determinated the kinetic constant of the hydrolisis reacion of ethyl acetate with NaOH, measuring condutivity values of the reaction mixture.
I used bidistillated water (high resisitivity), so its conductivity is negligible, but here is my question:

In case water you have has a non-negligible conductivity compared to the values from the reactants, could I just mesure the conductivity of the water I use, and substract that value from the experimental results?
As long as my knowledge allows me to think over, this makes sense, but I don't think I would be so simple aswell.

Thanks in advance

[Borek]

In case water you have has a non-negligible conductivity compared to the values from the reactants, could I just mesure the conductivity of the water I use, and substract that value from the experimental results?
As long as my knowledge allows me to think over, this makes sense, but I don't think I would be so simple aswell.

Makes sense, but you are guessing right - it is not the whole story. However, it would mostly matter for very precise measurements of the absolute values. In the kinetic studies you are mostly interested in the changes, so you can for most of the time ignore the fine print.

[curiouscat]

One problem could be swamping. If background is say 10,000 units and the effect is 5 units it is hard to measure by subtraction.

Don't know if that's true here.

[Altered State]

In case water you have has a non-negligible conductivity compared to the values from the reactants, could I just mesure the conductivity of the water I use, and substract that value from the experimental results?
As long as my knowledge allows me to think over, this makes sense, but I don't think I would be so simple aswell.

Makes sense, but you are guessing right - it is not the whole story. However, it would mostly matter for very precise measurements of the absolute values. In the kinetic studies you are mostly interested in the changes, so you can for most of the time ignore the fine print.

Could you tell me about those cases in which you are supposed to get that precise measurements?

[Borek]

Determining conductivity to measure concentration.

Not that I would ever use conductivity for this purpose.

[Altered State]

Determining conductivity to measure concentration.

Not that I would ever use conductivity for this purpose.

So if im asked that in an exam, I can say that for this kind of reaction rate constant experiment, it could be done that way, measuring and substracting water condutivity?

[Borek]

There is no simple "one size fits all" answer, see the curiouscat post.

In short: you have to take several things into account, and you have to think about what is going on in the solution.

[Altered State]

There is no simple "one size fits all" answer, see the curiouscat post.

In short: you have to take several things into account, and you have to think about what is going on in the solution.

I mean, in this case, in the solution we are supposed to have Ethyl acetate, NaOH (and its hydrolisis products) and water.

[Borek]

You have already answered your own question in the very first post, no idea what kind of answer you are looking for now.