Week 9 Wednesday lecture

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Megan Cao 1I
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Joined: Sat Sep 07, 2019 12:18 am

Week 9 Wednesday lecture

Postby Megan Cao 1I » Wed Mar 04, 2020 7:24 pm

In class today, we were calculating the rate law for [NOs]. the chemical equation was NO2 + CO --> NO + CO2 (all are gases). for the overall rate law we got K1[NO2]2. What happened to the CO? since we're supposed to include all reactants in the rate law, is it the zeroth order?

Matt Sanruk 2H
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Re: Week 9 Wednesday lecture

Postby Matt Sanruk 2H » Wed Mar 04, 2020 7:43 pm

Since it is not present in the slowest step we can assume that it is indeed zero order and does not affect the rate

Shail Avasthi 2C
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Re: Week 9 Wednesday lecture

Postby Shail Avasthi 2C » Thu Mar 05, 2020 8:04 pm

CO is not in the rate law because its concentration does not affect the rate of the reaction (i.e. it is zero order). This implies that CO is not involved in the slowest step of this multi-step reaction. It does not mean that CO is not involved in the reaction at all. Just that it's not significant to how fast the reaction proceeds.

BCaballero_4F
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Re: Week 9 Wednesday lecture

Postby BCaballero_4F » Mon Mar 09, 2020 5:21 pm

CO is zero order and because it is not in the slow step e assume its concentration does not have an affect overall

JohannaPerezH2F
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Re: Week 9 Wednesday lecture

Postby JohannaPerezH2F » Mon Mar 09, 2020 8:16 pm

yes it would be in the zeroth order

Matt Sanruk 2H
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Re: Week 9 Wednesday lecture

Postby Matt Sanruk 2H » Tue Mar 10, 2020 1:18 am

But a solvent is different right?

Jialun Chen 4F
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Re: Week 9 Wednesday lecture

Postby Jialun Chen 4F » Tue Mar 10, 2020 5:36 am

Matt Sanruk 2H wrote:Since it is not present in the slowest step we can assume that it is indeed zero order and does not affect the rate

I agree with Matt's rationale, the concentration of a zero-order has no effect on reaction.

John Liang 2I
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Joined: Fri Aug 30, 2019 12:18 am

Re: Week 9 Wednesday lecture

Postby John Liang 2I » Tue Mar 10, 2020 10:54 am

when we separated it out into fast and slow steps, we ignore the fast step reactants and products because these do not control the rate. an example used in class is when friends bake brownies with each person on a specific task, the rate of the production of brownies is dependent on the one slow friend, rather than the 5 other fast friends. hope this helps.


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