GCHM Question

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PooyaH

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For which one of the following mixtures is the ideal gas law most likely to produce accurate prediction of volume at STP?

A. HCl and HBr
B. HCl and NH3
C. HF and HCl
D. HF and CH4
E. HCl and CH4

Can some one explain this!? I have no clue about this one!
 
Yeah I also thought it was E...but I dont know why, my gut says so and I believe it, so it must be right 🙂
 
For which one of the following mixtures is the ideal gas law most likely to produce accurate prediction of volume at STP?

A. HCl and HBr
B. HCl and NH3
C. HF and HCl
D. HF and CH4
E. HCl and CH4

Can some one explain this!? I have no clue about this one!

B,c,d all hydrogen bond and would have intermolecular attractions which is a big no no for ideal gases. HCl and HBr both have polar covalent bonds so here would be some intermolecular attractions due to dipole dipole moments. Hope that helps pooya (the guy who loves his exlimation marks more than anyone on this board 🙂 )
 
nvm what i said was stupid...haha, shoombol is correct it has to do with intermolecular attractions and such...
 
For which one of the following mixtures is the ideal gas law most likely to produce accurate prediction of volume at STP?

A. HCl and HBr
B. HCl and NH3
C. HF and HCl
D. HF and CH4
E. HCl and CH4

Can some one explain this!? I have no clue about this one!

I picked E in my mind too without looking at the other posts. Of course the question is annoying, and would have maid me worried on DAT.
You have to look for the choice that has the weakest intermolecular forces [The ideal gas law assumes there are no intermolecular forces].
A,B and C have strong van der waals forces [between polar molecules]. HOwever, we have an unpolar molecule [CH4] in the last two choices. HCL is less polar that HF, so I would have chosen E.
 
OMG.this is hard.I felt so unprepared for this test.That is a conceptual Q that we can simply expect to get on the test and I thought of anything but what you just explained.Thanks.
 
B,c,d all hydrogen bond and would have intermolecular attractions which is a big no no for ideal gases. HCl and HBr both have polar covalent bonds so here would be some intermolecular attractions due to dipole dipole moments. Hope that helps pooya (the guy who loves his exlimation marks more than anyone on this board 🙂 )

Uhuuuh...Got it now.
Haha yeah I do use it a lot...btw, nice screen name buddy! 😀
 
I picked E in my mind too without looking at the other posts. Of course the question is annoying, and would have maid me worried on DAT.
You have to look for the choice that has the weakest intermolecular forces [The ideal gas law assumes there are no intermolecular forces].
A,B and C have strong van der waals forces [between polar molecules]. HOwever, we have an unpolar molecule [CH4] in the last two choices. HCL is less polar that HF, so I would have chosen E.

hey thanks for taking my explanation from 5 minutes earlier and rewording harrygt🙂
 
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would HF, HCl, and HBr all have dipole-dipole interactions correct?
CH4 would have dispersion forces, thats about it...
NH3 would have hydrogen bonding...
 
pooyajan 🙂, just beautiful question and honestly difficult one because you have to use the logic for answer. ok lets start 🙂
first you have to use difination of ideal Gas: do you remeber that?
small particle and intermolecule forces minimum( close to zero or you can assume zero).
second: hydrogyn bond( I am sure you are good about that F, O, N, then:
we can not choose " A" because HBr is big molecule compare to others.
B is incorrect because we have intraction : NH3 + Hcl====> NH4Cl
C and D are incorrect Because "HF" has hydrogyn bond between molecules( we want the least intraction between molecules).
and you know the answer now. 👍
maybe I am wrong. 🙂
 
pooyajan 🙂, just beautiful question and honestly difficult one because you have to use the logic for answer. ok lets start 🙂
first you have to use difination of ideal Gas: do you remeber that?
small particle and intermolecule forces minimum( close to zero or you can assume zero).
second: hydrogyn bond( I am sure you are good about that F, O, N, then:
we can not choose " A" because HBr is big molecule compare to others.
B is incorrect because we have intraction : NH3 + Hcl====> NH4Cl
C and D are incorrect Because "HF" has hydrogyn bond between molecules( we want the least intraction between molecules).
and you know the answer now. 👍
maybe I am wrong. 🙂

No buddy, you're right on
 
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