Download GENERAL CHEMISTRY II QUIZ 5 November 10, 2009

GENERAL CHEMISTRY II
QUIZ 5
November 10, 2009
INSTRUCTIONS:
PRINT YOUR NAME ————>
NAME
.
WORK 3 OF #1 THROUGH #4 (3 @ 25)
SHOW YOUR WORK FOR PARTIAL CREDIT
USE THE CORRECT NUMBER OF SIGNIFICANT FIGURES
THE LAST TWO PAGES ARE A PERIODIC TABLE
R = 0.08206 lit•atm/(mol•K)
R = 8.3145 J/mol•K
h = 6.626 X 10-34 J-s
1
2
.
.
3
.
c = 2.9979 X 108 m/s
4
.
J = (kg•m2)/s2
TOTAL(75)
____
.
1. A mixture of 0.10 mol of NO, 0.050 mol of H2, and 0.10 mol of H2O is placed in a 1.0
L vessel at 300 K.
The following reaction is allowed to come to equilibrium, and at equilibrium [NO] = 0.062M.
(a) Calculate the equilibrium concentrations of H2, N2, and H2O. and
(b) Calculate Kc
2NO(g) + 2H2(g)
N2(g)
+
2H2O(g)
2. The following oxidation reduction reaction occurs in aqueous solution at 25 °C.
If a solution that is 0.275 M in Fe(NO3)3 and 0.275 M in Ca(MnO4) is allowed to come to
equilibrium, what are the equilibrium concentrations of [MnO42-], [Fe3+], [MnO4-], and
[Fe2+]?
(assume [MnO4-]o = [Fe2+]o = 0.00 M)
MnO42-(aq) + Fe3+(aq)
MnO4-(aq) +
Fe2+(aq)
K = 3.18 x 103
3. The following reaction has a K value of 2.7 x 10-8 at 600 K. If 0.800 mol of N2 and
0.600 mol of O2 are placed in a 2.00 L flask at 600 K, what are the equilibrium
concentrations of all species?
N2(g) +
O2(g)
2NO(g)
4. The following reaction has a K value of 1.3 x 10+3 and an enthalpy of -17 kJ/mol at
1200 K. How would this system at equilibrium shift to restore equilibrium for each of
the following changes? (to the right, to the left, or no change)
UF6(g)
+
3H2O (g)
UO3(s)
+ 6HF(g)
(a) Water is added to the system ________________________
(b) UO3 is added to the system _________________________
(c) HF is removed from the system ______________________
(d) The volume is doubled _____________________________
(e) The temperature is increased _________________________
(f) Pressure is increased by adding helium __________________