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Old 06-14-2012, 10:15 PM   #1
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Default Strong Acid + Weak Base...no reaction?

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Hey guys,
This was a question I encountered in a TPR Gen Chem Passage.

Q: Titrating a solution of NH3 with a strong acid would result in:

A. A basic salt at the equivalence point
B. An acidic salt at the equivalence point
C. A neutral salt at the equivalence point
D. No reaction.

The correct answer is D, but I selected B. Why is D the answer? As far as I know, titrating a weak base with a strong acid should give an acidic salt at the equiv. point.
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Old 06-15-2012, 09:01 AM   #2
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Old 06-15-2012, 08:18 PM   #3
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Tricky, NH3=ammonia, is a liquid WITHOUT water. I don't know if that is why their is no reaction
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Old 06-15-2012, 08:20 PM   #4
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because you forgot to put the acid in a burette:P
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Old 06-15-2012, 09:22 PM   #5
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Quote:
Originally Posted by nabilesmail View Post
Tricky, NH3=ammonia, is a liquid WITHOUT water. I don't know if that is why their is no reaction
Ammonia's a gas. Regardless, there would be a reaction, I think this is just a typo
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Old 06-15-2012, 09:39 PM   #6
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What was their explanation?
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Old 06-16-2012, 09:37 AM   #7
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I was wrong~ or it could be D or B at this point
Last edited by Godric; 07-10-2012 at 08:22 AM.
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Old 06-19-2012, 06:02 PM   #8
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Hey guys, I apologize for the late response.

Their explanation was this:

NH3 is a weak base, and solution D is a strong acid. Therefore, the equivalence point will be in the acidic range, because when all the NH3 is neutralized, NH4Cl and H2O will remain. NH4Cl is an acidic salt.

Sh*t...re-reading their explanation makes me think that I actually got the answer right..it seems it was them who messed it up...

It sucks because this is not the first time I have come across with an error in these problems with TPR
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Old 06-19-2012, 08:14 PM   #9
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Quote:
Originally Posted by nabilesmail View Post
Tricky, NH3=ammonia, is a liquid WITHOUT water. I don't know if that is why their is no reaction
Quote:
Originally Posted by loveoforganic View Post
Ammonia's a gas. Regardless, there would be a reaction, I think this is just a typo
Also, the problem says a solution of ammonia, meaning ammonia dissolved in a solvent.

But yeah, D is incorrect.
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Old 06-19-2012, 08:51 PM   #10
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Yeah it should be acidic. You'll form NH4+, which is an acid.
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