Equilibrium law

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The equilibrium law makes it possible to answer quantitatively the questions: 'How far?' and 'In which direction?'.
 
Chemists use equilibrium constants to predict whether or not reactions tend to go.
 
It is important to bear in mind that even if a reaction tends to go it may yet go very slowly or not at all.

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Webguides

• Key ideas about chemical equilibrium

Recently Asked Questions

• If the reversible reaction: 2H₂O(g) --> 2H₂(g) + O₂(g) occurs at 1 atm pressure and 20% of the steam is converted to hydrogen and oxygen, how do we find the equilibrium partial pressures (in atm) of the components of the equilibrium? 140408
• I recently came across a question in a past examination paper which did not resemble any of the examples I had previously worked out. The question concerns homogeneous pressure equilibria, specifically the equilibrium reaction of the Haber process, N₂(g) + 3H₂(g) -> 2NH₃(g). The question read as follows: nitrogen and hydrogen are introduced into a vessel of fixed volume, each of partial pressure 2 atm. The vessel is maintained at 500 K when the gases react to form an equilibrium mixture having a total pressure of 3.6 atm. Estimate the partial pressures of all gases at equilibrium, and deduce a value for K_p for the equilibrium at 500 K. Any help with shedding some light on how to go about tackling this question would be much appreciated. 130408
• When extracting caffeine from a liquid, why are two small additions of trichloroethane used as opposed to one larger one? Is there a worked example available? 130408

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Tests

• The equilibrium law (A2)

updated: 21 August 2003