Unit 7 · Equilibrium

Chapter 7.5

Le Châtelier's Principle and the Reaction Quotient

Add product to an equilibrium mixture and the reaction runs backward until the same ratio is restored, as if it remembered the number. It does not remember anything; Q simply no longer equals K.

in preparation · lesson 33 of 45

By the end

  1. 01Predict the shift from adding or removing a species, changing volume, pressure, dilution, or temperature
  2. 02Predict observable consequences of a shift, such as a color or pH change
  3. 03Explain every shift as Q pushed away from K and the system restoring Q = K
  4. 04Distinguish disturbances that change Q from a temperature change that changes K

In unit 7

  1. 7.1Dynamic Equilibrium: When Nothing Seems to Change
  2. 7.2The Reaction Quotient and the Equilibrium Constant
  3. 7.3What the Size of K Tells You, and How K Values Combine
  4. 7.4Equilibrium Calculations and Particle Pictures
  5. 7.5Le Châtelier's Principle and the Reaction Quotient
  6. 7.6Solubility Equilibria and the Common-Ion Effect
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