How is the CO and N2 reaction written?

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Discussion Overview

The discussion centers around the chemical reaction between carbon monoxide (CO) and nitrogen (N2), specifically how to properly write the reaction and the associated thermodynamic properties. Participants explore the stoichiometry involved and the implications of using "stoichiometric amounts of air" in the context of the reaction.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant seeks clarification on how to write the reaction between CO and N2, indicating they have calculated the moles of CO but are uncertain about the reaction equation.
  • Another participant suggests that only CO reacts, implying N2 does not participate in the reaction.
  • A participant presents a balanced reaction of 2CO + O2 -> 2CO2 and discusses their calculations for the moles of CO and the enthalpy change, questioning the correctness of their results.
  • There is confusion regarding the sign of the enthalpy change, with one participant noting that their book presents a positive result, while they believe the reaction is exothermic.
  • Participants clarify that "stoichiometric amounts of air" refers to having enough oxygen to fully convert CO to CO2, with one participant asserting that the book's claim is incorrect based on their understanding of the reaction's exothermic nature.

Areas of Agreement / Disagreement

Participants express uncertainty about the correct representation of the reaction and the associated thermodynamic properties. There is disagreement regarding the interpretation of the enthalpy change and the book's claims about the reaction being endothermic.

Contextual Notes

Participants mention specific calculations and assumptions related to the reaction, including the enthalpy of formation values and the conditions under which the reaction occurs, but these remain unresolved and depend on the definitions used.

DottZakapa
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Homework Statement
Calculate the standard enthalpy change occurring when 2.00 m^3 (measured at 0,0 C and 1 atm) of a mixture with v/v % composition of 80.0% CO and 20.0% N2 react with a stoichiometric amount of air.
Relevant Equations
thermochemistry
Can anyone explain how is this reaction ? I 've evaluated the moles of CO and N2 but now i can't see how is this reaction written
CO + N2 ...?
 
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Hint: the only thing that reacts is CO.
 
Borek said:
Hint: the only thing that reacts is CO.
##2CO + O_{2(g)} -> 2CO_{2(g)} ## correct?
then I've found the moles of CO through ## n_{tot}= \frac {PV}{RT}=\frac {1atm * 2000L}{0,0821 \frac{atm*L}{mol*K}*273 K}##= 89.23 mol
Knowing that v/v%= ##\frac {n_i}{n_{tot}}*100##
##n_{CO}=\frac {80,0}{100}*89,23 mol##= 71,38 mol
##\Delta H°_{f\text{ }CO_2}= -393,5 \frac{KJ}{mol}##
##\Delta H°_{f\text{ CO}}= -110,5 \frac{KJ}{mol}##

##\Delta H°_r= 2*-393,5 \frac{KJ}{mol}+2* -110,5 \frac{KJ}{mol}##=-566 ##\frac{KJ}{mol}##

By proportion :
##\Delta H°_r= \frac {71,38\frac{KJ}{mol}}{2}*-566\text{ mol}##= ##-20*10^3\text { KJ}##

Is all this correct?
Why in the book the result is positive? how is this possible?
Could you please explain what should i think when i see "stoichiometric amounts of air"?
 
Stoichiometric amounts of air just means that you have sufficient oxygen to completely convert all of the CO to CO2.
Book seems to be wrong as this reaction is known to be exothermic.
 
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chemisttree said:
Stoichiometric amounts of air just means that you have sufficient oxygen to completely convert all of the CO to CO2.
Book seems to be wrong as this reaction is known to be exothermic.
thanks
 

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