### Rate of Reaction

Posted:

**Sun Feb 25, 2018 11:42 pm**Can someone explain why -d[NO2]/dt=d[NO]/dt=2 d[O2]/dt

I'm confused about the 2 before the d[O2]/dt

I'm confused about the 2 before the d[O2]/dt

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=145&t=28570

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Posted: **Sun Feb 25, 2018 11:42 pm**

Can someone explain why -d[NO2]/dt=d[NO]/dt=2 d[O2]/dt

I'm confused about the 2 before the d[O2]/dt

I'm confused about the 2 before the d[O2]/dt

Posted: **Sun Feb 25, 2018 11:46 pm**

In the chemical equation, the stoichiometric coefficients show that for every mol of O2 formed there are 2 mol of NO and NO2, so it O2 is forming half as fast. Thus, its rate would have to be doubled to equal the rate of NO being formed and NO2 being broken down.

Posted: **Sun Feb 25, 2018 11:46 pm**

The 2 is there due to the ratio of the coefficients between the reactants and the products.

Posted: **Sun Feb 25, 2018 11:51 pm**

Since the stoichiometric coefficients are 2 for NO2 and 1 for O2, the rate of O2 production will be half of that of NO2 depletion.

Posted: **Mon Feb 26, 2018 9:39 am**

you just need to pay attention to the coefficients, and since o2 is half, theres half as much made