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Equilibrium constant calculator

K and delta G are two ways of saying the same thing, joined by delta G = -RT ln K.

Standard free energy change
-11.4160kJ/mol
≈ Rounded Equilibrium constant
Temperature used
298.15 K
Show the working
  1. Equilibrium constant K = 100
  2. Temperature = 25
  3. Temperature used = 25 + 273.15 = 298.15
  4. Standard free energy change = -Rgas * 298.15 * ln(100) / 1000 = -11.416

Values are shown to six significant figures here; the arithmetic itself runs on exact fractions and is only rounded where a number is printed.

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    The formula

    • delta G0 = -R T ln K

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