Journal archive > 2005 > N 1 January-February

A new thermodynamic function, which allows easy determination of the direction of a reaction and its energetic characteristics

S. A. Bobrovnik

A new thermodynamic function, namely a universal variable Q, is suggested for the description of reversible chemical reactions. According to the definition, if the reaction is represented by the equation aA + bB = gG + hH, and K is the equilibrium constant, the universal variable Q is: Q = (aGgaHh)/(aAaaBbK). Then, Q is a dimensionless variable, which has the following properties: Q = 1 for the state of equilibrium, Q < 1 for spontaneous reactions, and Q > 1 for the reverse reaction. Knowledge of Q allows determination of the Gibbs energy and standard Gibbs energy by the same formula: ?G = RTlnQ.

Recieved: 2004-11-12

Published at the site: 2005-02-02

The original article in Ukrainian is available for download in PDF format.