How to Convert [I2] Concentration to [H+] Concentration?

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youmei0426
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Homework Statement


Printed text stating that the rate of acid-catalysed iodination of propanone can be followed by measuring how the concentration of iodine changes with time, with the equation I2(aq) + CH3COCH3(aq) → CH3COCH2I(aq) + H+(aq) + I-(aq).

Graph of [I2] in mol/dm^-3 against time in seconds, from 0 to 60 s, with cross-marked data points falling from about 0.72 at 10 s to about 0.35 at 60 s.


Homework Equations

The Attempt at a Solution


I need to know the time it takes for the [H+] concentration to be 0.15mol/L. However, the graph gives me the [I2] concentration over time, and I don't know how to convert it to the [H+] concentration. How should I solve the problem? Thanks!
 
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  • Printed text stating that the rate of acid-catalysed iodination of propanone can be followed by measuring how the concentration of iodine changes with time, with the equation I2(aq) + CH3COCH3(aq) → CH3COCH2I(aq) + H+(aq) + I-(aq).
    upload_2019-1-13_13-56-47.png
    4.8 KB · Views: 931
  • Graph of [I2] in mol/dm^-3 against time in seconds, from 0 to 60 s, with cross-marked data points falling from about 0.72 at 10 s to about 0.35 at 60 s.
    upload_2019-1-13_13-56-59.png
    8 KB · Views: 1,175
youmei0426 said:
don't know how to convert it to the [H+] concentration
Why would you want to do that ?
 
BvU said:
Why would you want to do that ?
I meant how to convert the known [H+] concentration to the [I2] concentration given to me by the graph. Because I need to know the time it takes for the hydrogen to reach the 0.15 mol/L concentration right?
 
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youmei0426 said:

Homework Statement


View attachment 237248
View attachment 237249

Homework Equations

The Attempt at a Solution


I need to know the time it takes for the [H+] concentration to be 0.15mol/L. However, the graph gives me the [I2] concentration over time, and I don't know how to convert it to the [H+] concentration. How should I solve the problem? Thanks!

I don't really understand what the question is, nor your answer.
[H+] = 0.015 mol/L at t = 0 aren't you told? It takes no time to get there.
The reaction rate looks to be constant. Have you tried to draw a straight line through it, or a least squares fit?
What do you understand by relative rate?
The chemical equation is telling you one mole of I2 that reacts produces how many moles of H+? Added to the store to number it is easy to know how many starting number it is easy to know how many m moles/L there are after any amount of reaction. Though whether this is relevant depends what the question is.
 
epenguin said:
2

I don't really understand what the question is, nor your answer.
[H+] = 0.015 mol/L at t = 0 aren't you told? It takes no time to get there.
The reaction rate looks to be constant. Have you tried to draw a straight line through it, or a least squares fit?
What do you understand by relative rate?
The chemical equation is telling you one mole of I2 that reacts produces how many moles of H+? Added to the store to number it is easy to know how many starting number it is easy to know how many m moles/L there are after any amount of reaction. Though whether this is relevant depends what the question is.
Oh I think I understand it now! I just need to draw the line of best fit and find the gradient of that line. Thanks!
 
The way the problem is worded I suppose the solution was buffered and pH was constant.
 
Borek said:
The way the problem is worded I suppose the solution was buffered and pH was constant.

I impliedXvideos Youporn Xhamster how to change over the known [H+] focus to the [I2] fixation given to me by the chart. Since I have to know the time it takes for the hydrogen to achieve the 0.15 mol/L focus right?
 
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