zero order reaction

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FrankieClarke2C
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zero order reaction

Postby FrankieClarke2C » Sun Mar 17, 2019 9:05 am

Why is it a zero order reaction with slope -k if the straight line fits to the data?

Briana Lopez 4K
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Re: zero order reaction

Postby Briana Lopez 4K » Sun Mar 17, 2019 9:28 am

The slope is -k because the integrated rate law for zero order is
-kt + [A]o = [A]

similar to the straight line y= mx + b

[A] = -kt + [A]o

Aili Ye 4L
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Re: zero order reaction

Postby Aili Ye 4L » Mon Mar 18, 2019 9:32 am

The integrated rate for a first order reaction is A= -kt + Ao which is in the form of a linear equation where -k is the slope.

Chantel_2I
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Re: zero order reaction

Postby Chantel_2I » Sun Mar 01, 2020 6:59 pm

A zero order equation integrated gives a first order equation, which when graphed, gives a straight line, as opposed to a second order equation, like something with x^2, that gives a parabola.

Jennifer Fuentes 2K
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Re: zero order reaction

Postby Jennifer Fuentes 2K » Wed Jan 26, 2022 10:59 pm

because rate is independent of reactant concentration, a graph of the concentration of any reactant as a function of time is a straight line with a slope of −k. The value of k is negative because the concentration of the reactant decreases with time. Conversely, a graph of the concentration of any product as a function of time is a straight line with a slope of k, a positive value.

Kimia Rategh 2A
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Re: zero order reaction

Postby Kimia Rategh 2A » Wed Mar 02, 2022 7:38 pm

Hi! Zero order reaction rates are independent on reaction concentrations, therefore we would have a reaction rate similar to y= mx +b where -k is the slope and the initial concentration is the intercept. Therefore, if the reaction is a zero order, then the data should fit the line with a slope of -k. Hope this helps!

Tammy Shen 2L
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Re: zero order reaction

Postby Tammy Shen 2L » Thu Mar 03, 2022 7:43 pm

A zero order reaction has the integrated rate law A=-kt+A0, which mimics the linear equation y=mx+b. This means that -k acts as the slope.

Zoe Dhalla 3I
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Re: zero order reaction

Postby Zoe Dhalla 3I » Sat Mar 05, 2022 4:47 am

Because rate is independent of reactant concentration, a graph of the concentration of any reactant as a function of time is a straight line with a slope of −k. The value of k is negative because the concentration of the reactant decreases with time. For a zero order reaction, as shown in the following figure, the plot of [A] versus time is a straight line with k = - slope of the line.

Heba Bounar 3K
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Re: zero order reaction

Postby Heba Bounar 3K » Sat Mar 05, 2022 6:48 pm

Hi! The integrated rate law of a zero order reaction is [A} = -kt +[A]o. This resembles the linear equation y = mx+b in which m represents slope. Therefore, -k represents the slope. Therefore, if a straight line is fit to the data ([A] vs time), then we know it is zero order and the slope is -k. Hope that helps!

Joellen 1B
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Re: zero order reaction

Postby Joellen 1B » Sun Mar 06, 2022 12:43 am

we know that the zero order reaction equation is A=-kt+A0, and it is similar to the equation y = mx +b where m represents the slope, so k would represent the slope and it is negative in this case.

Andrewtrung Le 3A
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Re: zero order reaction

Postby Andrewtrung Le 3A » Sun Mar 06, 2022 1:10 am

With a zero-order reaction, you've already recognized that the straight line fits to the data. Any line that is straight has a constant slope. Also, the slope is -k because k measures the rate at which reactants are used up - never can reactants increase in concentration when a chemical reaction progresses!

Andrewtrung Le 3A
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Re: zero order reaction

Postby Andrewtrung Le 3A » Sun Mar 06, 2022 1:10 am

With a zero-order reaction, you've already recognized that the straight line fits to the data. Any line that is straight has a constant slope. Also, the slope is -k because k measures the rate at which reactants are used up - never can reactants increase in concentration when a chemical reaction progresses!

Jeffrey Vo 2A
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Re: zero order reaction

Postby Jeffrey Vo 2A » Sun Mar 06, 2022 1:53 am

Hi Frankie, you already know that a zero order reaction has the equation of A=-kt+A0. This integrated rate law of a zero order reaction is akin to y=mx+b, where you can probably see that -k is the slope of A=-kt+A0. On a more conceptual level, the slope being negative is a result of the rate how how reactants are becoming products, so you can think about it being negative as there is a loss in reactants naturally in a chemical reaction just like how the concentration of products would have the value of k being positive.

Alice Weber 3I
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Re: zero order reaction

Postby Alice Weber 3I » Sun Mar 06, 2022 5:36 am

Hi, we would use this equation A=-kt+A0 which is similar to y=mx+b, therefore, -k is the slope.

Ashley Presnell 1C
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Re: zero order reaction

Postby Ashley Presnell 1C » Sun Mar 06, 2022 1:00 pm

This is because it is showing the concentration over time of the reaction, and since its linear it means the reagent is decreasing linearly over time which agrees with the zero order rules.

Jieun 2C
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Re: zero order reaction

Postby Jieun 2C » Sun Mar 06, 2022 7:44 pm

The slope is -k because A= -kt + Ao is in the form of y=mx+b where m=-k and m is the slope.

Kelly McFarlane
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Re: zero order reaction

Postby Kelly McFarlane » Sun Mar 06, 2022 8:05 pm

The reaction rate of a zero order reaction is [A]=-kt + [A]0 so following the rule y=mx+b, y is the y-axis ([A]), x is the x-axis (t), b is the y intercept ([A]0), and m is the slope (-k).

Nishan Reddy 3K
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Re: zero order reaction

Postby Nishan Reddy 3K » Sun Mar 06, 2022 10:37 pm

This is just the common way to represent the first order reaction where ln[A] = -kt + A0. This means that the reaction rate isn’t directly proportional to time.

Jacob_Eberson_2D
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Re: zero order reaction

Postby Jacob_Eberson_2D » Mon Mar 07, 2022 3:32 pm

the rate law for zero order is A=-kt+A0, which has the same format as the linear equation y=mx+b (with -k as the slope)

Morgan Micallef 1A
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Re: zero order reaction

Postby Morgan Micallef 1A » Mon Mar 07, 2022 3:51 pm

Hello! The intergrated equation for a zero-order reaction is A=-kt+A0. According to this equation, the slope of the line is -k

Isabelle Rieke-Wey 2G
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Re: zero order reaction

Postby Isabelle Rieke-Wey 2G » Mon Mar 07, 2022 3:53 pm

Hi!
the integrated equation for a zero-order reaction is A=-kt+A0, similar to y=mx+b which is why the slope is -k.

905740390
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Re: zero order reaction

Postby 905740390 » Mon Mar 07, 2022 8:27 pm

The zero-order reaction is A = -kt +A0 which tells us that the slope of this reaction is -k if you view this equation similar to y = mx + b

Konmal Ali 1G
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Re: zero order reaction

Postby Konmal Ali 1G » Tue Mar 08, 2022 11:23 am

A graph representing the concentration of any reactant as a function of time is a straight line with a slope of k since rate is independent of reactant concentration. Because the concentration of the reactant falls with time, the value of k is negative.

Aanjaneyaa
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Re: zero order reaction

Postby Aanjaneyaa » Tue Mar 08, 2022 4:15 pm

Since, there is integration involved, it ends up being the zero order reaction becomes a first order equation. The zero order reaction is A=-kt+A0, and based on the equation y=mx+b, m=-k, so the slope is -k.

Anish_Marripati_2F
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Re: zero order reaction

Postby Anish_Marripati_2F » Tue Mar 08, 2022 4:17 pm

Because rate is independent of reactant concentration, a graph of the concentration of any reactant as a function of time is a straight line with a slope of −k. The value of k is negative because the concentration of the reactant decreases with time

605823283
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Re: zero order reaction

Postby 605823283 » Wed Mar 09, 2022 12:00 pm

it is an intergrated rate law

Neha Mukund
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Re: zero order reaction

Postby Neha Mukund » Thu Mar 10, 2022 11:59 pm

When one observes the equation to the zero order rate law, A = -kt +A0, it can be seen that the slope is -k. Hope that helps.

Alejandra Hernandez 2A
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Re: zero order reaction

Postby Alejandra Hernandez 2A » Fri Mar 11, 2022 12:08 am

Hi!! A reaction that's zero-order has the integrated rate law of A=-kt+A0, this law mimics the linear equation y=mx+b (or uses it as a model). This means that -k acts as the 'm' aka the slope. Hope this helped!! :)

gwenkelley3L
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Re: zero order reaction

Postby gwenkelley3L » Fri Mar 11, 2022 12:12 am

since the integrated equation for a zero order reaction is A = -kt+A0, the slope is -k since this equation is very similar y = mx+b

Sophia Hartwell 1F
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Re: zero order reaction

Postby Sophia Hartwell 1F » Fri Mar 11, 2022 12:17 am

Hi there! So because there is integration involved, the zero order reaction becomes a first order equation. The zero order reaction is A=-kt+A0, and the slope is -k based on the equation y=mx+b, m=-k.


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