2018 AP Chem FRQ answers
scribd.com/document/378757346/2018-AP-Chemist...
scribd.comPosted May 10, 2018, 1:58 AM UTC
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scribd.comIsn’t your reactant mixture on question 2 incorrect? it asked for the reactant mixture of NO(g) and O2(g) that would produce the product box.
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dude that's not my paper... it's jacob's paper... and i agree i thought the same thing
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I think there are some errors but i fucked up a lot lol. Im ready for that 1 lol.
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this made me less confident for a 5 tbh
that curve better be a 76%
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Foreal but either way im stuck with a bitch ass (projected) 3
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Yes. I drew down NO2 molecules by mistake. The work to the right indicates the proper ratios.
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[deleted]
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International is different
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lol you are welcome
Why isn't the enthalpy change for 1e i) considered negative? Didn't the temperature of the water increase, meaning it should be negative?
1e. is not asking for the enthalpy change; it is asking for the heat change involved.
To be clear, if you made it negative, you're probably fine, but it is conventionally given as a positive quantity, where a +q means temperature of the system increases, and a -q means the temperature of the system decreases (q is, of course, directly and positively proportional to the temperature change).
Oh, I'm probably just remembering the question wrong then. Thanks for the explanation!
https://apcentral.collegeboard.org/pdf/ap18-frq-chemistry.pdf
yo... why is the delta H for number 1 not -300kj/mol? i got confused on that btw
The heat evolved is dictated by the extent to which the reaction proceeds. If you ignore the concept of limiting reagent, your answer is off by a factor of four. The enthalpy change is proportional to coefficients as stoichiometric ratios.
Shit. Isn't it just kj/mol reactant?? and we pick one reactant that works?
Also for number 2 isnt the initial total pressure 1 atm? or is the individual pressure of each 1 atm?
Sure. But you need to account for how much of it reacts and account for the coefficient. Not all the reactants are consumed completely here.
No. It says each is at a pressure of 1 atm. That phrasing means each was at an individual partial pressure of 1 atm.
Oh it's you that wrote it? Lmao