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Chemical Equilibria |
Chemical equilibrium is the state of a reaction system in which the rate of product formation equals the rate of product decomposition. The equilibrium constant (or formation constant), K, is equal to the ratio between the forward and reverse rate constants. Equilibrium constants depend on temperature, pressure, ionic strength (for aqueous solutions), etc, and can be determined from:
There are many literature sources of equilibrium constants and of thermodynamic data
A global reaction is the sum of single-step reactions. The following table shows an example with two reactions between a central group, M (for example a metal ion) and a ligand L:
M + L ![]() ML + L ![]() |
(single-step reactions) | |
M + 2 L ![]() |
(global reaction) |
The equilibrium constant for the global reaction is often denoted by the Greek letter beta
M + L |
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ML + L |
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M + 2 L |
To draw an equilibrium diagram you need: