Q. 8.65

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William Lan 2l
Posts: 73
Joined: Fri Sep 29, 2017 7:07 am

Q. 8.65

Postby William Lan 2l » Thu Jan 18, 2018 9:56 pm

Can someone explain how to approach this problem without being given an initial reaction? Are we supposed to find the initial reaction ourselves?

David Minasyan 1C
Posts: 54
Joined: Thu Jul 13, 2017 3:00 am

Re: Q. 8.65

Postby David Minasyan 1C » Thu Jan 18, 2018 10:09 pm

This is a highly simplified version but:
1) go to appendix 2A and find the NO reaction and the enthalpy for it
2) using that reaction and the two reactions given, rearrange them so that things cancel out and all that's left on the product side is dinitrogen pentoxide.
3) Make sure you adjust the enthalpy values as you change the reactions (so halve the enthalpy value if you multiply rxn coefficients by .5)
4) Add it all up

104969854
Posts: 36
Joined: Fri Sep 29, 2017 7:05 am

Re: Q. 8.65

Postby 104969854 » Thu Jan 18, 2018 10:23 pm

Make sure to double the equation 2NO+O2==>2NO2 and double the enthalpy as well. Cancel NO2 on both sides and then once you have a resulthing equation, use the bond enthapies to calculate the kJ. Ensure to account for moles!!


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