Prentice Hall
© 2003
LOHS
AP Chem Schrempp 2008
2
•Consider colorless frozen N2O4.
At room temperature, it decomposes to brown NO2:
N2O4(g) ® 2NO2(g).
•At some time, the color stops changing and we have a mixture of N2O4 and NO2.
•Chemical equilibrium is the point at which the concentrations of all species are
constant.
The Concept of Equilibrium