Claudio GIOMINIa,
Giancarlo MARROSUa,
Mario E. CARDINALIb and
Angelica PAOLUCCIb
aLa Sapienza University of Rome, (Italy), ICMMPM Department, Italy
bUniversity of Perugia (Italy), Department of Chemistry, Italy
For some gaseous equilibria, with particular stoichiometric characteristics, the addition of some reactant or products, as large as it may be, when operated under constant temperature and pressure, cannot cause a (practically) complete shift of the equilibrium to the right, or to the left. The effect of the addition is counteracted by the increase of volume that the system undergoes to keep constant the pressure. [Chem. Educ. Res. Pract. Eur.: 2000, 1, 145-149]