to determine the overall reaction
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to determine the overall reaction
To determine the overall reaction with multiple steps, do you cancel the molecules that appear on both reactant and product side and what are leftover are the overall reaction, regardless the relative speed of individual steps? For example, on question 14.105, we got the overall reaction by canceling molecules that appear on both sides of the arrows, disregarding the speed of each step. Is that how we determine the overall reaction? Thanks!
Re: to determine the overall reaction
I just finished this problem too… Yes, the overall reaction is determined that way by adding all three reactions and canceling what's on both sides.
The rate of reaction is determined by the slowest step, which in this case is the 2nd step (very slow). Intermediates cannot be in the rate law, so you must write out the rate law for the first reaction and substitute it in for the intermediate.
The rate of reaction is determined by the slowest step, which in this case is the 2nd step (very slow). Intermediates cannot be in the rate law, so you must write out the rate law for the first reaction and substitute it in for the intermediate.
Re: to determine the overall reaction
yay ok thank you! I have another question, when you are writing out the rate law do you not put H2O in it? for example, on 105 when you are using the rate law of the first step to substitute for intermediate, H2O is being omitted.
Thank you!
Thank you!
Re: to determine the overall reaction
In dilute solutions where H2O is the solvent, it can be omitted because the concentration does not noticeably change.
Re: to determine the overall reaction
why is it that for the overall rate law we can leave in the concentration of OH-; shouldn't it be written off somehow because it's an intermediate?
Re: to determine the overall reaction
OH- is left in the rate law because it's concentration is so small (from the fact that [H3O+]=[OH-]= 10^-7) that it does have influence.
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