Sulaiman
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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?
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blogfast25
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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]
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