Equilibrium – Chapter 15

Slide 1

Equilibrium Chapter 15

Equilibrium is achieved when forward and reverse reaction rates are equal.aA + bB cC + dD

Watch this animation http://www.youtube.com/watch?v=LMIbJ-B92Ho[X] = concentration of species X in molarityPx = pressure of gas X in atmospheres

ex Write the equilibrium constant for the following reaction:2NO(g) + Cl2(g) 2NOCl(g)

ex The reaction of N2 with O2 to form NO might be considered a means of "fixing" nitrogen:N2(g) + O2(g) 2NO(g)Determine the K for:2NO N2 + O2

for 4NO 2N2 + 2O2

Kp is the equilibrium expression in terms of pressure for a reaction involving only gases. It is not necessarily equal to Kc.

Kp = Kc(RT)n

n = sum of the coefficients of the gas products - sum of the coefficients of the gas reactants.

ex SnO2(s) + 2CO(g) Sn(s) + 2CO2(g)

Applications of KK >> 1equilibrium lies to the right, products favored

K KQ = K equilibriumQ < K

Ex - At 448oC the equilibrium constant for the following reaction, Kc, is 50.5.H2(g) + I2(g) 2HIPredict the direction in which the reaction will proceed to reach equilibrium at 448oC if we start with 0.020 mol of HI, 0.010 mol of H2 and 0.030 mol of I2 in a 2.0 L container.

Calculation of Equilibrium Concentrationsex For the Haber process,N2(g) + 3H2(g) 2NH3(g)

Kp = 1.45x10-5 at 500oC. In an equilibrium mixture of the three gases at 500oC, the partial pressure of H2 is 0.928 atm and that of N2 is 0.432 atm. What is the partial pressure of NH3 in the equilibrium mixture?

ex A 1.000 L flask is filled with 1.000 mol of H2 and 2.000 mol of I2 at 448oC. The value of Kc at this temperature is 50.5. What are the equilibrium concentrations of H2, I2, and HI?

Here is the quiz

https://docs.google.com/spreadsheet/embeddedform?formkey=dDM4ODY2LWJKVGdXM2dnQXdkTjBrbUE6MQ