how did we determine that reactant C was a zero-order reactant?
Thanks!
Sapling Question
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Re: Sapling Question
Hi! To determine the order of C, look for two experiments where the initial concentrations of A and B are the same, but the initial concentration of C is different. Therefore, we look at experiments 1 and 4 since the initial concentrations of A and B are the same between both experiments, but the initial concentration of C is different. Even though the initial concentration of C differs from experiment 1 to 4, the initial rate of the reaction is the same which suggests that the concentration of C does not affect the reaction rate. Therefore, C is a zero-order reactant. Hope this helps! :)
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Re: Sapling Question
If we are trying to determine the order of the reactant, C, we want to look at the two data rows where A and B remain constant, but C changes. As such, we want to look at Rows 1 and 4. We can see that even when the concentration of C changes, the rate remains the same. This is indicative of a zero-order process, meaning that Reactant C is zero-order.
Re: Sapling Question
Look at experiments 1 and 4. Since A and B were the same and C was different, the change in the rate would be the order of C. SInce the rate didn't change then C is 0 order.
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Re: Sapling Question
Hi! To determine any reactant's order, you want to choose to compare between 2 reactions where the only value that changes is the reactant's concentration.
Looking at the reactions given, we can see that for Experiment 1 and 4, the values of A and B stay the same, while the value of C changes. Just quickly looking at it, we see that as the value of C changes, the initial rate does not change. Therefore, we can infer that C does not have any effect on the initial rate, so its order must be 0.
Another (and more reliable) way to do this is to divide rate law of 1 by rate law of 4, or vice versa. each rate law is rate=[A]^n [B]^m [C]^l, and so when dividing rate law 1 by rate law 4, we can plug in the initial rates and the concentrations of each compound. From there, we can see that the concentrations of [A] and [B] cancel each other out, leaving rate1/rate4= [concentration of C1]^l/[concentration of C2]^l, and rate1/rate4 is equal to 0. Then just solve for l, and you should get the same answer. Hope this helped!
Looking at the reactions given, we can see that for Experiment 1 and 4, the values of A and B stay the same, while the value of C changes. Just quickly looking at it, we see that as the value of C changes, the initial rate does not change. Therefore, we can infer that C does not have any effect on the initial rate, so its order must be 0.
Another (and more reliable) way to do this is to divide rate law of 1 by rate law of 4, or vice versa. each rate law is rate=[A]^n [B]^m [C]^l, and so when dividing rate law 1 by rate law 4, we can plug in the initial rates and the concentrations of each compound. From there, we can see that the concentrations of [A] and [B] cancel each other out, leaving rate1/rate4= [concentration of C1]^l/[concentration of C2]^l, and rate1/rate4 is equal to 0. Then just solve for l, and you should get the same answer. Hope this helped!
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Re: Sapling Question
I think the way we are trying to figure out this value for C. Is through a system of equations almost comparing two equation with only C. So equations 1 and 4. Values of A and B are the same which is a form of isolating C. Therefore when comparing the two A, B and k can be canceled out because both equations share these values.
From there we get C^c=12.8 and C^c=12.8 Divide the two and we get C^c/C^c=12.8/12.8 Which gives 1=1 We know that anything to power 0 is 1. So it makes sense that C is in zero order.
Do the same with A and B to isolate and follow some produre. remember C is zero is always 1
From there we get C^c=12.8 and C^c=12.8 Divide the two and we get C^c/C^c=12.8/12.8 Which gives 1=1 We know that anything to power 0 is 1. So it makes sense that C is in zero order.
Do the same with A and B to isolate and follow some produre. remember C is zero is always 1
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Re: Sapling Question
In this problem, we found the orders of C by comparing reactions in which A and B were held constant while C changed.
Comparing experiments 1 and 4 which fulfilled these requirements found that while the concentration of C changed, the initial rate did not. This means that changing the concentration of C did not affect the rate.
Therefore, we can conclude that C was zero order.
Comparing experiments 1 and 4 which fulfilled these requirements found that while the concentration of C changed, the initial rate did not. This means that changing the concentration of C did not affect the rate.
Therefore, we can conclude that C was zero order.
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Re: Sapling Question
You can see that C changes throughout the experiment at seemingly random intervals while other variables are changing as well, showing that its concentrations has no effect on the rate law
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Re: Sapling Question
If you compare experiments 1 and 4 where reactants A and B are constant and the concentration of C changes, the rate still stays the same. This means that the concentration of C has no effect on the rate, meaning it is 0th order. [C]^0 in the rate law = 1, so the rate law just depends on the concentrations of A and B!
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