Unique Reaction Rates  [ENDORSED]


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Justin Chu 1G
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Unique Reaction Rates

Postby Justin Chu 1G » Wed Feb 28, 2018 5:21 pm

Such as in 15.3C and 15.5, I just wanted some clarification on what "unique" rate of a reaction means.

Nina Gautam 1K
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Re: Unique Reaction Rates

Postby Nina Gautam 1K » Wed Feb 28, 2018 5:52 pm

It's a unique reaction rate because it is the same for all concentrations of reactants and products when it is multiplied by their stoichiometric coefficient. The species doesn't need to be specified when writing a unique rate.

Chem_Mod
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Re: Unique Reaction Rates

Postby Chem_Mod » Thu Mar 01, 2018 7:38 pm

I will discuss this in class tomorrow.

AVERAGE RATE = (CONC(t2) − CONC(t1))/(t2 −t1) = ∆CONC/∆t

INSTANTANEOUS RATE = −(d[R])/dt
OR
INSTANTANEOUS RATE = (d[P])/dt

AVERAGE & INSTANTANEOUS RATES CAN BE DIFFERERENT FOR THE INDIVIDUAL R & P.
THINK OF THEM AS THE EXPERIMENTALLY MEASURED RATES (COLLECTED DATA) OVER LONG TIME INTERVALS (∆) OR SHORT TIME INTERVALS (d).

UNLIKE THE UNIQUE RATE WHICH IS CALCULATED AND IS THE SAME FOR ALL R & P IN THAT ‘UNIQUE’ REACTION WHERE:

UNIQUE RATE = −1/a (d[A])/dt = 1/b (d[B])/dt = 1/c (d[C])/dt

IN THE REACTION: a A ---> b B + c C

Hopefully this clarifies.

Stay warm and see you in class!

Magdalena Palavecino 1A
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Re: Unique Reaction Rates

Postby Magdalena Palavecino 1A » Sat Mar 03, 2018 12:41 pm

Does this mean that even if all the stoichiometric coefficients were different, because of the concentrations of each species then all rates would be the same? And does unique rate refer to the equality of all rates or of one species only?

Anika_Patel_1G
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Re: Unique Reaction Rates  [ENDORSED]

Postby Anika_Patel_1G » Sat Mar 03, 2018 9:19 pm

If all of the stoichiometric coefficients were different, the unique rate can still be the same using any of them to calculate it because we are multiplying the (change in concentration/change in time) by 1/coefficient. This therefore allows us to calculate the unique rate using any of the species in the reaction. The unique rate refers to the one rate calculated using one of the species. The equality formula is just to show that it does not matter which one you choose as long as you multiple by 1/coefficient and negate the equation if it is a reactant.

Leah Thomas 2E
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Re: Unique Reaction Rates

Postby Leah Thomas 2E » Sun Mar 04, 2018 9:55 pm

I'm still confused as to how we know when to use the instantaneous rate and the unique rates?

Peter Dis1G
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Re: Unique Reaction Rates

Postby Peter Dis1G » Sun Mar 04, 2018 10:35 pm

I think instantaneous rate is the general but more accurate measure of the rate of change of concentration, and unique rate is like the instantaneous rate of individual species. (so the name 'unique')

Dang Lam
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Re: Unique Reaction Rates

Postby Dang Lam » Tue Mar 06, 2018 1:02 pm

Anika_Patel_1G wrote:If all of the stoichiometric coefficients were different, the unique rate can still be the same using any of them to calculate it because we are multiplying the (change in concentration/change in time) by 1/coefficient. This therefore allows us to calculate the unique rate using any of the species in the reaction. The unique rate refers to the one rate calculated using one of the species. The equality formula is just to show that it does not matter which one you choose as long as you multiple by 1/coefficient and negate the equation if it is a reactant.

Thank you so much! your response is very helpful

mayasinha1B
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Re: Unique Reaction Rates

Postby mayasinha1B » Wed Mar 07, 2018 11:38 am

I'm pretty sure the unique rate is the same for every reactant, so you just wouldn't take the stoichiometric coefficients into account.

Yeyang Zu 2J
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Re: Unique Reaction Rates

Postby Yeyang Zu 2J » Sun Mar 11, 2018 12:32 pm

I will say the rate of a chemical reaction is the change in concentration over the change in time and is a metric of the "speed" at which a chemical reactions occurs.
And Unique rate is the rate occurs per unit of each molecules

Abby Ellstrom 1I
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Re: Unique Reaction Rates

Postby Abby Ellstrom 1I » Mon Mar 12, 2018 6:30 pm

A unique rate is the same for all of the materials in the reaction (products and reactants) because it multiplies the change in substance by one over its coefficient.

Josh Moy 1H
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Re: Unique Reaction Rates

Postby Josh Moy 1H » Tue Mar 13, 2018 7:29 pm

It's a unique reaction rate because its the same for all concentrations of reactants and products when multiplied by their stoichiometric coefficient.

Rishi Khettry 1L
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Re: Unique Reaction Rates

Postby Rishi Khettry 1L » Tue Mar 13, 2018 10:08 pm

The unique reaction rate depends on the coefficients of the reaction

Michael Downs 1L
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Re: Unique Reaction Rates

Postby Michael Downs 1L » Fri Mar 16, 2018 7:47 pm

Thanks!

Jordanmarshall
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Re: Unique Reaction Rates

Postby Jordanmarshall » Fri Apr 27, 2018 2:28 pm

what is the reaction rate??

Jocelyn1B
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Joined: Fri Apr 06, 2018 10:04 am

Re: Unique Reaction Rates

Postby Jocelyn1B » Sun Apr 29, 2018 3:40 pm

The reaction rate is the measure of change in concentration of the reactants or the change in concentration of the products per unit time.

Zack Barta 3I
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Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Tue Oct 16, 2018 2:39 pm

Thanks!

Zack Barta 3I
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Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Tue Oct 23, 2018 12:15 pm

What is the reaction rate?

Lucy Agnew 3E
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Re: Unique Reaction Rates

Postby Lucy Agnew 3E » Fri Oct 26, 2018 8:51 am

These explanations were very helpful! Totally forgot about this !

Arlene Linares 3A
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Re: Unique Reaction Rates

Postby Arlene Linares 3A » Thu Nov 08, 2018 3:39 pm

Chem_Mod wrote:I will discuss this in class tomorrow.

AVERAGE RATE = (CONC(t2) − CONC(t1))/(t2 −t1) = ∆CONC/∆t

INSTANTANEOUS RATE = −(d[R])/dt
OR
INSTANTANEOUS RATE = (d[P])/dt

AVERAGE & INSTANTANEOUS RATES CAN BE DIFFERERENT FOR THE INDIVIDUAL R & P.
THINK OF THEM AS THE EXPERIMENTALLY MEASURED RATES (COLLECTED DATA) OVER LONG TIME INTERVALS (∆) OR SHORT TIME INTERVALS (d).

UNLIKE THE UNIQUE RATE WHICH IS CALCULATED AND IS THE SAME FOR ALL R & P IN THAT ‘UNIQUE’ REACTION WHERE:

UNIQUE RATE = −1/a (d[A])/dt = 1/b (d[B])/dt = 1/c (d[C])/dt

IN THE REACTION: a A ---> b B + c C

Hopefully this clarifies.

Stay warm and see you in class!



Thank you for the information

705022748
Posts: 26
Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby 705022748 » Thu Nov 15, 2018 10:54 am

Unique rate depends on the stoichiometric coefficient, but stays the same for all products and reactants in the reaction.

Zack Barta 3I
Posts: 33
Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Sun Nov 25, 2018 3:17 pm

Very Helpful!

Zack Barta 3I
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Re: Unique Reaction Rates

Postby Zack Barta 3I » Sun Nov 25, 2018 3:18 pm

Very Helpful!

Mariah Hill
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Re: Unique Reaction Rates

Postby Mariah Hill » Mon Nov 26, 2018 12:12 am

The unique rate has to do with the stoichiometric coefficients because it stays the same (proportionality)

705022748
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Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby 705022748 » Mon Nov 26, 2018 12:46 am

The unique rate stays constant for all reactants and depends on coefficients of the reaction.

105002507
Posts: 30
Joined: Thu Sep 27, 2018 11:15 pm

Re: Unique Reaction Rates

Postby 105002507 » Sun Dec 02, 2018 1:02 pm

The unique rate depends on the stoichiometric coefficient & stays the same for all products and reactants

Zack Barta 3I
Posts: 33
Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Sun Dec 02, 2018 8:38 pm

Thanks!

Zack Barta 3I
Posts: 33
Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Sun Dec 02, 2018 8:38 pm

Thanks!

Zack Barta 3I
Posts: 33
Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Sun Dec 02, 2018 8:38 pm

Thanks!

Zack Barta 3I
Posts: 33
Joined: Thu Sep 27, 2018 11:25 pm

Re: Unique Reaction Rates

Postby Zack Barta 3I » Sun Dec 02, 2018 8:39 pm

Thanks!


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