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Topic: circle diagrams giving me a hard time  (Read 9277 times)

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Offline student8607

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circle diagrams giving me a hard time
« on: January 31, 2009, 05:41:23 PM »
diagram a: 6 red circles
diagram b: 12 red circles
diagram c: 9 red circles

question 1: what are the relative rates of decomposition?
2:4:3?

question 2: what are the relative half lives?
how am I to know this? there aren't any times given?

question 3: how will the half lives be affected if the volume in each vessel is decreased by factor of 2
half lives only depend on k & sometimes concentration - so they wouldn't be affected?

Offline student8607

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Re: circle diagrams giving me a hard time
« Reply #1 on: January 31, 2009, 05:44:23 PM »
diagram a @ 0 min: 8 red circles
diagram b @ 1 min: 6 red circles, 2 blue circles
diagram c @ 2 min: 4 red circles, 4 blue circles

question 1: what is the order of the reaction?
how am I to know this? i don't have reaction rates to compare to my changes in concentration?

question 2: suppose each sphere represented 6.0 x 1021 molecules and that the volume was 1.0L. what is the rate constant?
once I know the order I might be able to handle this

Offline student8607

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Re: circle diagrams giving me a hard time
« Reply #2 on: February 03, 2009, 02:33:21 PM »
anyone?

Offline Astrokel

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Re: circle diagrams giving me a hard time
« Reply #3 on: February 03, 2009, 02:49:48 PM »
Lol, pardon me what is a circle diagram?
No matters what results are waiting for us, it's nothing but the DESTINY!!!!!!!!!!!!

Offline student8607

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Re: circle diagrams giving me a hard time
« Reply #4 on: February 03, 2009, 02:57:36 PM »
They are just these drawings of boxes filled with red and blue balls.

Offline sjb

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Re: circle diagrams giving me a hard time
« Reply #5 on: February 03, 2009, 03:39:57 PM »
diagram a @ 0 min: 8 red circles
diagram b @ 1 min: 6 red circles, 2 blue circles
diagram c @ 2 min: 4 red circles, 4 blue circles

question 1: what is the order of the reaction?
how am I to know this? i don't have reaction rates to compare to my changes in concentration?

question 2: suppose each sphere represented 6.0 x 1021 molecules and that the volume was 1.0L. what is the rate constant?
once I know the order I might be able to handle this

Consider that the reaction is red circles going to blue circles, then you have a change in number of red circles over time.

As to your first question, I honestly have no real idea

Offline Astrokel

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Re: circle diagrams giving me a hard time
« Reply #6 on: February 03, 2009, 04:48:21 PM »
Quote
diagram a @ 0 min: 8 red circles
diagram b @ 1 min: 6 red circles, 2 blue circles
diagram c @ 2 min: 4 red circles, 4 blue circles

question 1: what is the order of the reaction?
how am I to know this? i don't have reaction rates to compare to my changes in concentration?

Well red and blue circles seem bit confusing. Let's simplify it.

Imagine there is this reaction taking place   R  ::equil:: B

Initially, [R] = 8 and [B ] = 0

As you have mentioned, you have to calculate reaction rate to determine the order of reactant.

So at the 1st min, the reaction rate would be -(6-8)/1 = 2
              2nd min, the reaction rate would be -(4-6)/1 = 2

What does a constant reaction rate tells you about the order of [A] if you were to compare it against with the concentration?
No matters what results are waiting for us, it's nothing but the DESTINY!!!!!!!!!!!!

Offline student8607

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Re: circle diagrams giving me a hard time
« Reply #7 on: February 05, 2009, 05:34:42 PM »
Well changing the concentrations doesn't affect the rate, so perhaps it is 0 order?

Offline Astrokel

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Re: circle diagrams giving me a hard time
« Reply #8 on: February 05, 2009, 07:48:37 PM »
Quote
Well changing the concentrations doesn't affect the rate, so perhaps it is 0 order?
;D
No matters what results are waiting for us, it's nothing but the DESTINY!!!!!!!!!!!!

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