अंशांकन वक्र कैलकुलेटर — सूत्र

Van't Hoff Equation

The van't Hoff equation predicts how the equilibrium constant changes with temperature.

Formula

ln(K2/K1) = (delta_H/R) × (1/T1 - 1/T2)

where R = 8.314 J/(mol·K) is the gas constant and delta_H is the reaction enthalpy.

  • Exothermic reactions (delta_H < 0): K decreases as T increases
  • Endothermic reactions (delta_H > 0): K increases as T increases

    • This is the thermodynamic basis for Le Chatelier's principle regarding temperature.

    हल किया गया उदाहरण

    An exothermic reaction with K=100 at 298 K, delta_H = -50 kJ/mol. Find K at 350 K.

    1. ln(K2/K1) = (-50000/8.314) × (1/298 - 1/350)
    2. 1/298 - 1/350 = 0.003356 - 0.002857 = 0.000499
    3. ln(K2/K1) = -6013.4 × 0.000499 = -3.001
    4. K2/K1 = exp(-3.001) = 0.0498
    5. K2 = 100 × 0.0498 = 4.98