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       #Post#: 1073--------------------------------------------------
       Chem kinetics question im stuck in:-(
   DIR By: Chris
       Date: November 9, 2012, 4:42 am
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       Here's the question:
       Nitric oxide reacts with oxygen to give NO2
       2NO + O2 -> 2NO2
       The rate law is rate=k[NO]^2[O2]
       Where k=1.16*10^-5 at 339'C.
       A vessel contains NO and O2 at 339'C. The initial partial
       pressures of NO and O2 are 155mmHg and 345mmHg, respectively.
       What is the rate of decrease of partial pressure of NO in mmHg
       per second.
       My attempt is:
       rate=k(NO]^2[O2]
       PV=nRT
       n/V = P/RT
       Concentration=P/RT,
       R=8.314, T=273+339=612K
       When i substitute the P/RT into rate law, i get Rate=7.3*10^-10
       but the answer in my book is 6.6*10^-8
       where am I getting it wrong?
       
       #Post#: 1114--------------------------------------------------
       Re: Chem kinetics question im stuck in:-(
   DIR By: Michel
       Date: November 13, 2012, 8:59 am
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       Hint: dP/dt=dP/dC x dC/dT
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