課程名稱︰分析化學一
課程性質︰化學系大二必修
課程教師︰林萬寅
開課學院：理學院
開課系所︰化學系
考試日期（年月日）︰2011.01.10
考試時限（分鐘）：110 mins
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
1.是非題:每題2分,答錯倒扣1分,不答0分
(i) D2-lamp is commonly used as the light source for visible spectra.
(ii) The detector response is wavelength-dependent.
(iii) Zeeman correction in atomic spectroscopy requires the use of an
electric field.
(iv) For a given excited state, triplet state has lower energy than singlet
state.
(v) Mirror-image rule. applies to the fluorescence and phosphorescence
spectra.
(vi) Quartz cuvets are normally used for infrared measurements.
(vii) Thermocouple can be used to detect infrared radiation.
(viii)X-ray usually has a greater energy than γ-ray.
(ix) Pure rotational spectra fall in the microwave region.
(x) Temperature stability is more critical for atomic absorption than for
atomic emission.
2. Give the correct answers to each problem; 2 points for each answer.
(1) Name any two types of detectors for detecting UV-visible radiation.
(ii) Name two electronic transitions that involve the change of spin state.
(iii) Name any two possible types of interferences in atomic spectroscopy
(iv) Give an advantage and a disadvantage of decreasing monochromator slit
width.
(v) Name the two mechanisms of line broadening in atomic spectroscopy.
3. Answer the following questions; 5 points for each question.
A) Describe how a laser works.
B) Describe the principle of operation for a hollow cathode lamp
C) Describe the procedures for the enzyme-linked immunosorbent assay (ELISA)
D) Describe the method of continuous variation to determine the stoichiometry
of a metal complex.
4. The absorbances for 1.00 x 10^-4 M Mn04-, 1.00 x 10 M Cr207 2-,
and an unknown mixture of the two compounds (all in a 1.00-cm cell)
are given below.
Wavelength (nm) Mn04- standard Cr2072- standard Mixture
266 0.095 0.420 0.676
320 0.386 0.088 0.542
(A) Find the molar absorptivities for both species. 4%
(B) Find the concentrations of the two compounds in the mixture. 6%
(C) Find the percentage of transmitted light for the mixture at 320 nm. 2%
5. Answer the following questions concerning a diffraction grating.
(A) With a resolution of 20000. how close in cm-1 is the closest line to
400.0 nm that can barely be resolved? 4%
(B) Calculate the second-order resolution of a grating that is 5.0 cm long
and is ruled at 1000 lines/mm. 4%
(C) Find the angular dispersion (Δψin degrees) between 400.0 and 400.5 nm
for second-order diffraction from a grating with 5000 lines/mm and
ψ=15degree. 4%
6. Answer the following questions according to the energy diagram (rotational
states and higher vibrational states are not shown) of a molecule given
below.
(A) Name the corresponding processes for A~E 10%
(B) The rate constant for D,E,and Kq are 4.0*10^8 s-1 ,1.0*10^8 s-1 and
5.0*10^10 M-1s-1,respextively,Find
(i) the lifetime of the molecule in the absence of the quencher
(ii)the quantum tield of the molecule in the presence of 0.010 M quencher 6%
answers
1. 是非題；每題2分，答錯倒扣 1分，不答0分。
(i) X (ii) O (iii) X (iv) O (v) X
(vi) X (vii) O (viii)X (ix) O (x) X
2. Give the correct answers to each problem; 2 points for each answer.
(i) photomultiplier tube; photodiode array detector; charge coupled device;
or charge injection device (any two of them)
(ii) intersystem crossing; phosphorescence
(iii) spectral, chemical, and ionization interferences (any two)
(iv) advantage: better resolution; disadvantage: weaker intensity
(or noisy spectrum).
(v) Doppler and pressure broadening.
3. Answer the following questions; 5 points for each question.
(A)
1. The lasing medium in a cavity is placed inbetween two mirrors
2. One mirror reflects all light; the other transmits ~1% of light
3. Pump the lasing medium to achieve a population inversion between two
states
4. Emitted photons bounce back & forth between mirrors & stimulate emission
of more photons for great amplification of light
5. Intense light (laser) comes out of the mirror with ~1% transmittance.
(B)
1. The glass tube is filled with (1-5 torr) Ar
2. Apply high voltage to ionize Ar
3. Ar+ is accelerated toward the cathode coated with the element of interest
4. It sputters atom of interest into the gas phase
5. Atoms excited by collisions with electrons emit atomic lines of correct
frequency (with narrower linewidth)
(C)
1. Antibody-1 (Ab-1) of analyte is bonded to a polymer (substrate)
2. Analyte (or antigen) is added; unbound analyte was washed away
3. Add enzyme-linked Ab-2; unbound Ab-2 was washed away
4. Substrate is added; colored or fluorescent product is formed
5. Measure the absorbance or fluorescence of product to determine [analyte]
(D)
1. Vary [L]:[M] & keep [M]+[L] constant
2. Measure the corrected absorbance of each solution
3. Acorrected = Ameasured – εMbXM εXbXL; XM, XL: mole fraction of M & L
4. Plot Acorrected vs. XL (assume εMLn > εM & nεL)
5. XL of maximum absorbance > stoichiometry of MLn
4
(A) ε(MnO4–) = 950; ε(Cr2O72–) = 4200 at 266 nm 2%
ε(MnO4–) = 3860; ε(Cr2O72–) = 880 at 320 nm 2%
(B) [MnO4–] = 1.48 × 10^-4 M [Cr2O72–] = 1.36 ×10^-4 M 6%
(C) T = 10^–A = 0.287 29% of light was transmitted 2%
5
(A) Δλ=1.25cm-1
(B) 50*1000*2=100000
(C) Δφ=0.15度
6
(A)
A absorption
B vibrational relaxation VR
C internal conversion+VR
D internal conversion+VR
E fluorescence
(B) 2.0ns
(C) 0.10
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