課程名稱︰普通化學甲上
課程性質︰化學系必帶
課程教師︰周必泰
開課學院：理學院
開課系所︰化學系
考試日期（年月日）︰2008/01/18
考試時限（分鐘）：130min
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
期中考相關題目(50分)
(20) 1. Name the following conpounds(2 points each):
(a). KHCO3, (b). K2CO3, (c). H2SO3, (d). H2SO4, (e). NaClO, (f). NaClO4,
(g). KMnO4, (h). CdSe, (i)有刻度量筒, (j).拋棄式滴管
(15) 2. For the van-der Waals equation of the real gas
nRT n
P = ------ - a(---)^2
clac V-nb V
in which P is the pressure calculated from van-der Waals equation.
clac
(a). Please derive the above equation from the idea gas law.(10)
(b). At higher pressure such as >1000atm, P calculated from the van-der Waals
equation shows significant deviation from the observed one. Give a
reasonable explanation.(5)
(10) 3. When water is supercooled, it freezes at a temperature below 0.0'C. If
10.9kJ of heat is released when 2.00 mol of supercooled water at -15.0'C
freezes, calculate the molar enthalpy of fusion for ice at 0.0'C and 1 atm.
Assume the molar heat capacities for H2O(s) and H2O(l) are 37.5J/K*mol and
75.3J/K*mol, respectively, and are temperature independent.
(5) 4. The mean-free path λ (distance/collision) for the gas He can be
expressed as λ = kT/σP√2 for the gas He, in which σ denotes the collision
cross section, please calculate the collision frequency of He in terms of P, k,
_ _
T and c (c is the mean speed)
期末考以後的題目(100分)
(20)5. Explain the definition(5 points each)
a. Galvanic Cell and Electrolytic Cell
b. Cathodic protection
c. What is the major difference between corrosion of iron and aluminum?
d. Explain difference between combustion engine and fuel cell.
(20)6.
(a) 由 G=H-TS的定義, 試導出G和pressure(P) and temperature(T)的相關性為:
dG=VdP-SdT, in which V denotes volume and S is system entropy at 25'C
(b) On the above basis and common sense, explain why you need to make diamond
from graphite at high temperature and high pressure, giving
diamond o
CO2(g) --> C(s) + O2(g) ΔG = 397kJ
graphite o o
CO2(g) --> C(s) + O2(g) ΔG = 394kJ at 25 C.
(10)7. Calculate ΔH' for each of the following reactions, using the data
attached below:
4Na(s) + O2(g) -> 2Na2O(s)
2Na(s) + H2O(l) -> 2NaOH(aq) + H2(g)
2Na(s) +CO2(g) -> Na2O(s) + CO(g)
Explain why a water or carbon dioxide fire extinguisher might not be effective
in putting out a sodium fire.
o
Substance and State ΔHf (kJ/mol)
Na2O(s) -416
NaOH(aq) -476
H2O(l) -286
CO2(g) -393.5
CO(g) -110.5
(10)8. One method for synthesizing CH3OH is via the process
CO(g) + 2H2(g) -> CH3OH(l)
o o o
ΔGf[CH3OH(l)]=-166kJ ΔGf[H2(g)]=0kJ ΔGf[CO(g)]=-137kJ
Calculate the ΔG at 25'C for this reaction, in which carbon monoxide gas at
5.0 atm and hydrogen as at 3.0 atm are converted to liquid methanol.
(R=8.3145JK^-1mol^-1 = 0.08206L*atmK^-1mol^-1)
(10)9. Consider a 2.00-mol sample of Ar at 2.00 atm and 298K.
a. If the gas sample expands adiabatically and reversibly to a pressure of
1.00atm, calculate the final temperature of the gas sample assuming ideal
gas behavior.
b. If the gas sample expands adiabatically and irreversibly against a constant
1.00 atm pressure, calculate the final temperature of the gas sample
assuming ideal gas behavior.
(10)10. Combine the equations
o o o o o
ΔG = -nFε and ΔG = ΔH - TΔS
to drive an expression for ε0 as a function of temperature. Describe how one
can graphically determine ΔH0 and ΔS0 from measurements of ε0 at different
temperatures. Assume thet ΔH0 and ΔS0 do not depend on temperature.
(10)11. The overall reaction in the lead storage battery is
Pb(s) + PbO2(s) + 2H+(aq) + 2HSO4-(aq) -> 2PbSO4(s) +2H2O(l)
a. Calculate ε at 25'C for this battery when [H2SO4] = 4.5M; that is, [H+] =
[HSO4-] = 4.5M. At 25'C, ε0=2.05V for the lead storage battery.
b. For the cell reaction ΔH0=-315.9kJ and ΔS0=263.5J/K. Calculate ε0 at
-20'C.
c. Calculate ε at -20'C when [H2SO4]=4.5M.
d. Based on you previous answers, why does it seem that batteries fail more
often on cold days than on warm days?
(10)12. A silver concentratino cell is set up at 25'C with 1.0M AgNO3 in the
left compartment and 1.0M NaCl along with excess AgCl(s) in the right
compartment. The measured cell potintial is 0.58V. Calculate the Ksp value
for AgCl at 25'C.
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