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 1:32 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 7:30 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 8:29 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 11:08 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 8:47 pm

Thanks!

Jordanmarshall
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Re: Unique Reaction Rates

Postby Jordanmarshall » Fri Apr 27, 2018 3:28 pm

what is the reaction rate??

Jocelyn1B
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Re: Unique Reaction Rates

Postby Jocelyn1B » Sun Apr 29, 2018 4:40 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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Re: Unique Reaction Rates

Postby Zack Barta 3I » Tue Oct 23, 2018 1:15 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 9:51 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
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Joined: Fri Sep 28, 2018 12:25 am

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
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Joined: Fri Sep 28, 2018 12:25 am

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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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
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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

ran2000
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Joined: Fri Sep 28, 2018 12:15 am

Re: Unique Reaction Rates

Postby ran2000 » Sat Mar 09, 2019 7:10 pm

The unique reaction rate is defined as the rate of the increase in product concentration or the rate in decrease of product concentration divided by the stoichiometric coefficient.

riddhiduggal
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Joined: Fri Sep 28, 2018 12:21 am

Re: Unique Reaction Rates

Postby riddhiduggal » Fri Mar 15, 2019 10:51 pm

When do we use the instantaneous rate versus the unique rates?

Ashley P 4I
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Re: Unique Reaction Rates

Postby Ashley P 4I » Sat Mar 16, 2019 1:21 pm

riddhiduggal wrote:When do we use the instantaneous rate versus the unique rates?

I am also still really confused on this. If I find out, I’ll let you know.

204929947
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Joined: Fri Apr 06, 2018 11:03 am

Re: Unique Reaction Rates

Postby 204929947 » Sat Mar 16, 2019 11:13 pm

what is the difference between the instantaneous rate and the unique rate law??

NicoJones_1B
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Joined: Fri Aug 09, 2019 12:16 am

Re: Unique Reaction Rates

Postby NicoJones_1B » Sun Oct 13, 2019 11:20 am

In what situations and types of problems will we have to use instanteous reaction rates?

AnayaArnold_3L
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Joined: Wed Sep 18, 2019 12:19 am

Re: Unique Reaction Rates

Postby AnayaArnold_3L » Sun Oct 27, 2019 10:06 pm

Thank you for clarifying!
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!

005162902
Posts: 102
Joined: Wed Sep 18, 2019 12:15 am

Re: Unique Reaction Rates

Postby 005162902 » Mon Oct 28, 2019 11:51 am

Peter Dis1G wrote: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')


unique rate is is the same for all reactants because of its coefficients

Mitchell Koss 4G
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Re: Unique Reaction Rates

Postby Mitchell Koss 4G » Mon Nov 04, 2019 3:41 pm

Combustion is also unique in that it will always have some reactants and some products that remain the same. (CO2, H2O)

AnayaArnold_3L
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Re: Unique Reaction Rates

Postby AnayaArnold_3L » Mon Nov 11, 2019 7:31 pm

Thank you
Mitchell Koss 4G wrote:Combustion is also unique in that it will always have some reactants and some products that remain the same. (CO2, H2O)

Maggie Eberhardt - 2H
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Re: Unique Reaction Rates

Postby Maggie Eberhardt - 2H » Thu Mar 12, 2020 1:31 pm

so in problems like 7A.3, we just take the unique rate and multiply it by the stoichiometric coefficient to determine the rate of each reactant/product right? just clarifying here, since I'm not 100% confident on the concept of unique rates

805421690
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Re: Unique Reaction Rates

Postby 805421690 » Wed Dec 16, 2020 10:35 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.

Wow this clarified a lot thank you!

Lorena_Morales_1K
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Re: Unique Reaction Rates

Postby Lorena_Morales_1K » Sun Feb 28, 2021 11:31 pm

What does a unique reaction rate mean again?

JasmineReyes-2K
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Joined: Fri Sep 24, 2021 6:12 am

Re: Unique Reaction Rates

Postby JasmineReyes-2K » Sat Jan 22, 2022 3:44 pm

Hi!,

A unique reaction rate is the increase or decrease in product concentration that is defined by our stoichiometric coefficient

Jennifer Fuentes 2K
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Re: Unique Reaction Rates

Postby Jennifer Fuentes 2K » Sun Jan 23, 2022 10:56 am

A unique rate is a rate of appearance/disappearance of any of the species in a reaction divided by its stoichiometric coefficient. A unique rate will be the same for each reactant or product.

Neha Jonnalagadda 2D
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Joined: Fri Sep 24, 2021 7:06 am

Re: Unique Reaction Rates

Postby Neha Jonnalagadda 2D » Thu Feb 10, 2022 2:21 pm

The unique rate is the same for all coefficients so you wouldnt balance the equation first.

505801516
Posts: 34
Joined: Mon Jan 09, 2023 9:08 am

Re: Unique Reaction Rates

Postby 505801516 » Sun Jan 22, 2023 9:07 pm

its unique because the reaction rate is the same for each concentration of products and reactions when it gets multiplied by the stoich coefficient.

Julianne_Sue_3A
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Re: Unique Reaction Rates

Postby Julianne_Sue_3A » Sun Jan 29, 2023 11:44 pm

Have we seen an example of this in the current 14B classes? I couldn't find an example in the lectures so I'm wondering where I can look for more practice.

Thanks!

505801516
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Joined: Mon Jan 09, 2023 9:08 am

Re: Unique Reaction Rates

Postby 505801516 » Sun Mar 19, 2023 12:39 am

a unique reaction rate entails the rat being the same for the concentrations of both the products and the reactants when that reaction rate is multiplied by the coefficient that goes with it. there is no need to specify a species when you are writing a reaction rate.

306060519
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Joined: Fri Sep 29, 2023 11:29 am

Re: Unique Reaction Rates

Postby 306060519 » Sun Oct 15, 2023 11:12 pm

You need to look at the overall system and then translate the mole content

705721552
Posts: 38
Joined: Fri Sep 29, 2023 11:56 am

Re: Unique Reaction Rates

Postby 705721552 » Wed Oct 18, 2023 10:51 pm

Will we be tested on the exceptions for the periodic table.

705721552
Posts: 38
Joined: Fri Sep 29, 2023 11:56 am

Re: Unique Reaction Rates

Postby 705721552 » Sun Oct 29, 2023 11:15 pm

What are some text book problems that can help me with reaction rates?

705721552
Posts: 38
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Re: Unique Reaction Rates

Postby 705721552 » Sun Nov 26, 2023 3:46 pm

What will be some indicators in word problems that would suggest that the reactions are unique?


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