1. At the start of a reaction, there are 0.249 mol N2, 3.21 X 10 -2 mol H2, and 6.42 X 10 - 4 mol NH3 in a 3.50 L reaction vessel at 375 oC. If the equilibrium constant (Kc) for the reaction
N2 (g) + 3 H2 (g) ←→2 NH3 (g)
is 1.2 at this temperature, decide whether the system is at equilibrium. If it is not, predict which way the net reaction will proceed.
2. The equilibrium constant Kc for the reaction:
H2 (g) + I2 (g) ←→ 2 HI (g)
is 54.3 at 430 oC. Suppose that in a certain experiment we place 0.243 mole of H2, 0.146 mole I2 and 1.98 moles of HI all in a 1.00 L container at 430 oC. Will there be a net reaction to form more H2 and I2 or more HI?
3. The equilibrium constant (Kc) for the formation of nitrosyl chloride, an orange-yellow compound, from the nitric oxide and molecular chlorine
2 NO (g) + Cl2 (g) ←→2 NOCl (g)
is 6.5 x 10 4 at 35 oC. In a certain experiment, 2.0 X 10 -2 mole of 8.3 x 10 -3 mole of Cl 2 and 6.8 moles of NOCl are mixed in a 2.0- L flask. In which direction will the system proceed to reach equilibrium?
Labels: Chemistry Lecture, Sample Problems
