# don't understand what is exchanging with what in this acid/base equilibrium

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NH4

the same reaction can be written as:

NH4

I assume that at pH=7, the likely case is:

NH4

where (k

1 Question. NH4

If NH4

NH4

where (k

If NH

NH

where (k

2 Question. What is the relationship between k

Depending on the answer to 1st question, I would like to get something like this: k

^{+ }+ H_{2}O (k_{r}) = (k_{f}) NH_{3 }+ H_{3}O^{+};the same reaction can be written as:

NH4

^{+ }+ HO^{-}(k_{r}) = (k_{f}) NH_{3 }+ H_{2}O;I assume that at pH=7, the likely case is:

NH4

^{+ }+ H_{2}O (k_{r}) = (k_{f}) NH_{3 }+ H_{3}O^{+}where (k

_{f}) - rate constant of forward reaction and (k_{r}) - rate constant of reverse reaction.1 Question. NH4

^{+ }or NH_{3 }is exchanging H^{+ }with H_{2}O?If NH4

^{+ }is exchanging H^{+ }with H_{2}O:NH4

^{+ }(k_{-1}) =(k_{1}) H_{2}O, transfer of H^{+ }between them.where (k

_{1}) - pseudo first order rate constant of H^{+ }transfer from NH4^{+ }to H_{2}O and (k_{-1}) - pseudo first order rate constant of H^{+ }transfer from H_{2}O to NH4^{+}.If NH

_{3}is exchanging H^{+ }with H_{2}O:NH

_{3}(k_{-1}) =(k_{1}) H_{2}O, transfer of H^{+ }between them.where (k

_{1}) - pseudo first order rate constant of H^{+ }transfer from NH_{3}to H_{2}O and (k_{-1}) - pseudo first order rate constant of H^{+ }transfer from H_{2}O to NH_{3}.2 Question. What is the relationship between k

_{1}, k_{-1}and k_{f}, k_{r}?Depending on the answer to 1st question, I would like to get something like this: k

_{1}=k_{r}*[NH_{3 }]
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#2

(Original post by

NH4

the same reaction can be written as:

NH4

where (kf) - rate of forward reaction and (kr) - rate of reverse reaction.

1 Question. NH4

If NH4

NH4

where (k

If NH

NH

where (k

2 Question. What is the relationship between k

**alex_alex**)NH4

^{+ }+ H_{2}O (kr) = (kf) NH_{3 }+ H_{3}O^{+};the same reaction can be written as:

NH4

^{+ }+ HO^{-}(kr) = (kf) NH_{3 }+ H_{2}O;where (kf) - rate of forward reaction and (kr) - rate of reverse reaction.

1 Question. NH4

^{+ }or NH_{3 }exchanging with H_{2}O?If NH4

^{+ }is exchanging with H_{2}O:NH4

^{+ }(k_{-1}) =(k_{1}) H_{2}O,where (k

_{1}) - rate of exchange from NH4^{+ }to H_{2}O and (k_{-1}) - rate of exchange from H_{2}O to NH4^{+}.If NH

_{3}is exchanging with H_{2}O:NH

_{3}(k_{-1}) =(k_{1}) H_{2}O,where (k

_{1}) - rate of exchange from NH_{3}to H_{2}O and (k_{-1}) - rate of exchange from H_{2}O to NH_{3}.2 Question. What is the relationship between k

_{1, }k_{-1 and }k_{f}, k_{r}?kn (n can be anything) is the rate constant for the forward reaction, e.g. NH3 + H3O+ -> NH4+ + H2O

k(-n) is the rate constant of the reverse process. NH4+ + H2O -> ......

K is the overall equilibrium constant, note that the rate constant isn't capitalised. How you have put the rate constants in (i.e. in with one side of the reaction) makes no sense. It isn't possible to put down the proper notation in this format, you have to write it really, but it is....

You have the kn and k(-n) notations above and below the equilibrium sign matching with which wa the arrows point in the eq symbol. This should mean kn is above.

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(Original post by

Your notation is all wrong. This may be because of having to type it or maybe because you have it wrong.

kn (n can be anything) is the rate constant for the forward reaction, e.g. NH3 + H3O+ -> NH4+ + H2O

k(-n) is the rate constant of the reverse process. NH4+ + H2O -> ......

K is the overall equilibrium constant, note that the rate constant isn't capitalised. How you have put the rate constants in (i.e. in with one side of the reaction) makes no sense. It isn't possible to put down the proper notation in this format, you have to write it really, but it is....

You have the kn and k(-n) notations above and below the equilibrium sign matching with which wa the arrows point in the eq symbol. This should mean kn is above.

**JMaydom**)Your notation is all wrong. This may be because of having to type it or maybe because you have it wrong.

kn (n can be anything) is the rate constant for the forward reaction, e.g. NH3 + H3O+ -> NH4+ + H2O

k(-n) is the rate constant of the reverse process. NH4+ + H2O -> ......

K is the overall equilibrium constant, note that the rate constant isn't capitalised. How you have put the rate constants in (i.e. in with one side of the reaction) makes no sense. It isn't possible to put down the proper notation in this format, you have to write it really, but it is....

You have the kn and k(-n) notations above and below the equilibrium sign matching with which wa the arrows point in the eq symbol. This should mean kn is above.

Please, do not change the reaction direction, because originally:

NH

_{4}Cl = NH

_{4}

^{+}+ Cl

^{-. }

The notation I used to differentiate between reaction rate constant (kf, kr) and H

^{+ }exchange rate constant (k1, k-1). I am trying to establish a relationship between them. I am not sure I understand NH

_{4}

^{+}or NH

_{3}is exchanging H

^{+}with H2O?

At pH=7, I assume that 1st one is the most likely case. NH4

^{+ }+ H

_{2}O (kr) = (kf) NH

_{3 }+ H

_{3}O

^{+};

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#4

(Original post by

Please, do not change the reaction direction, because originally:

NH

The notation I used to differentiate between reaction rate constant (kf, kr) and H

At pH=7, I assume that 1st one is the most likely case. NH4

**alex_alex**)Please, do not change the reaction direction, because originally:

NH

_{4}Cl = NH_{4}^{+}+ Cl^{-. }The notation I used to differentiate between reaction rate constant (kf, kr) and H

^{+ }exchange rate constant (k1, k-1). I am trying to establish a relationship between them. I am not sure I understand NH_{4}^{+}or NH_{3}is exchanging H^{+}with H2O?At pH=7, I assume that 1st one is the most likely case. NH4

^{+ }+ H_{2}O (kr) = (kf) NH_{3 }+ H_{3}O^{+};Please actually define what you mean by NH3 exchanging with H2O etc. This doesn't mean anything specific. I could guess but I'm not going to potentially waste our time when you could write it out properly.

(NH3 = H2O is not an acceptable equation to write... write out fully what you mean)

Also you probably need the relation K=kn/k(-n) to answer some of your questions.

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(Original post by

It doesn't matter which direction you put the reaction. If anything I have put it the right way as the hydronium is way more acidic than ammonium and placing this on the right implies the opposite (but only implies, doesn't actually mean it is)

Please actually define what you mean by NH3 exchanging with H2O etc. This doesn't mean anything specific. I could guess but I'm not going to potentially waste our time when you could write it out properly.

(NH3 = H2O is not an acceptable equation to write... write out fully what you mean)

Also you probably need the relation K=kn/k(-n) to answer some of your questions.

**JMaydom**)It doesn't matter which direction you put the reaction. If anything I have put it the right way as the hydronium is way more acidic than ammonium and placing this on the right implies the opposite (but only implies, doesn't actually mean it is)

Please actually define what you mean by NH3 exchanging with H2O etc. This doesn't mean anything specific. I could guess but I'm not going to potentially waste our time when you could write it out properly.

(NH3 = H2O is not an acceptable equation to write... write out fully what you mean)

Also you probably need the relation K=kn/k(-n) to answer some of your questions.

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#6

(Original post by

I tried to detail the question as much as I could. Please, reread the original question description. I hope it is now clear I am trying to do. Please, let me know if I still did not manage to clarify something. Thank you for your time.

**alex_alex**)I tried to detail the question as much as I could. Please, reread the original question description. I hope it is now clear I am trying to do. Please, let me know if I still did not manage to clarify something. Thank you for your time.

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