[CHEM]reaction direction

[ippie]

NH3 + H2O -> NH4(+) + OH(-)
What direction does this reaction go?
help~

---

Members don't see this ad.

 

[bigstix808]

NH3 + H2O -> NH4(+) + OH(-)
What direction does this reaction go?
help~

depends on the pH of the solution. but seeing how we have no other information, the equation is going to move to the right becaues NH3 is a weak base and has a pKa ~ 9-10ish (pKb ~ 4-5).

 

[113zami]

why wouldn't the rxn go in the opposite direction?

 

[joey2007]

I thought this reaction goes in both directions...

 

[hoss19]

depends on the pH of the solution. but seeing how we have no other information, the equation is going to move to the right becaues NH3 is a weak base and has a pKa ~ 9-10ish (pKb ~ 4-5).

i think you mean nh4 has pka 9-10. ammonia has pka of 36. likely then, the rxn will proceed towards weaker acid (water) and base (ammonia).

 

[bigstix808]

i think you mean nh4 has pka 9-10. ammonia has pka of 36. likely then, the rxn will proceed towards weaker acid (water) and base (ammonia).

oops...my b ...ruff morning

 

[War Eagle]

Left

 

[bigstix808]

sorry about the mixing up of numbers...but anyway, about this question...we do not have enough information to gage which way the rxn will procede. If NH3 is added to water, there is going to be at least some of it that will cause the rxn to the right to take place because an ammoina solution is basic. but once the Keq has been met, the solution will remain in equalibrium until Le Chatleir's principle must come into play.

 

[hoss19]

sorry about the mixing up of numbers...but anyway, about this question...we do not have enough information to gage which way the rxn will procede. If NH3 is added to water, there is going to be at least some of it that will cause the rxn to the right to take place because an ammoina solution is basic. but once the Keq has been met, the solution will remain in equalibrium until Le Chatleir's principle must come into play.

not to beat a dead horse here, but i think the heart of the question is to tell which way the rxn goes based on acid / base strength...and we all know from orgo 1 that a rxn proceeds towards weaker acid / base....remember?

 

[bigstix808]

not to beat a dead horse here, but i think the heart of the question is to tell which way the rxn goes based on acid / base strength...and we all know from orgo 1 that a rxn proceeds towards weaker acid / base....remember?

that's what i figured...i wasn't trying to disprove anyone...i just have a tendency to over analyze stuff.