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Topic: Effect of temperature on NH3/NH4 ratio system  (Read 4131 times)

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Offline 21385

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Effect of temperature on NH3/NH4 ratio system
« on: March 31, 2008, 10:40:39 PM »
What is the effect of increasing temperature on the NH3/NH4+ system?

This may look like an easy question if one thinks that it can be solved through chemical equations but if you look here

NH3 + H2O => NH4+ + OH-
NH4+ + H2O =>NH3 + H3O+
These are the reactions that are happening
These equations are both endothermic and if you increase the temperature, both equations will shift to the right, meaning that there are two contradicting effects.

Can anyone come up with alternative explanation?

Thanks a lot, I really need this urgently
« Last Edit: April 01, 2008, 02:31:34 AM by 21385 »

Offline Borek

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Re: Effect of temperature on NH3/NH4 ratio system
« Reply #1 on: April 01, 2008, 03:51:09 AM »
IMHO you can't answer this question without exact numerical data about temperature dependence of both Kw and ammonia Kb.
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Offline 21385

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Re: Effect of temperature on NH3/NH4 ratio system
« Reply #2 on: April 01, 2008, 05:50:11 PM »
Umm....I was wondering if you can note that as temperature increases, the solubility of NH3 decreases. Thus, if the question asks for the concentration of NH3, then, the concentration of NH3 decreases. Although le Chatelier's principle will change NH4+ into NH3, there is no doubt that the concentration of NH3, as well as NH4+ will decrease.

Is this correct?

Thanks a lot

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