Sulaiman
International Hazard
Posts: 3628
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
How to determine which way will it go?
In the thread 'KCL from KNO3' blogfast 25 made the statement;
'The equilibrium for HCl + HNO3 === > NOCl lies much to the left.'
How do I look at a chemical equation and work out which paths are most favourable?
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by Sulaiman  | In the thread 'KCL from KNO3' blogfast 25 made the statement;
'The equilibrium for HCl + HNO3 === > NOCl lies much to the left.'
How do I look at a chemical equation and work out which paths are most favourable? |
It's not really a question of 'which path'.
Take a simple, generic case:
A < === > B
This is an equilibrium reaction, once equilibrium is achieved A is converted to B and B is also converted back to B, simultaneously. At equilibrium
the following condition applies:
K = [B]/[A] with K the equilibrium constant and [A]/[B] the ratio of concentrations of A and B.
If [A] is small and [B] large, then K is large and the equilibrium is said to be left leaning.
If [A] is large and [B] is small then K is small and the equilibrium is said to be right leaning.
The constant K is calculated from ΔG (for A === > B) and Nernst's Derivation.
[Edited on 25-5-2015 by blogfast25]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
