110年 - [無官方正解]110 國立嘉義大學_碩士班招生考試試題_應用化學系：分析化學#146632

1. All of the following methods are used for the argentometric titrations, EXCEPT? (3%)(A) Volhard’s method (B) Haber’s method(C) Fajan’s method (D) Mohr’s method(E) None of the above

2. Which of the following analytical methods would be most appropriate to analyze amixture containing analytes with low volatility and moderate polarity? (3%)(A)X-ray (B) Gas chromatography(C) Precipitation titration (D) High performance liquid chromatography(E) UV-Vis spectroscopy

3. An impure sample of K₂O was analyzed by precipitating the potassium as theinsoluble tetraphenyl borate salt, KB(C₆H₅)_4. The precipitate, KB(C₆H₅)₄ has amass of 3.14 g. What is the mass of K₂O in the original sample? (Molar masses:KB(C₆H₅)₄ = 358.3 g and K₂O = 94.2 g) (3%)(A) 0.413 g (B) 0.826 g(C) 1.651 g (D) 2.423 g(E) None of the above

4. Infrared spectroscopy is useful for determining certain aspects of the structure oforganic molecules because (3%)(A) all molecular bonds absorb IR radiation.(B) IR peak intensities are related to atomic number and molecular mass.(C) most organic functional groups absorb in a characteristic region of the IRspectrum.(D) vibrational transitions are correlated to spin-spin coupling.(E) all of the above.

5. A constant current of 0.800 A is used to deposit copper at the cathode of anelectrolytic cell. How many coulombs would be required to reduce 2 mol of Cu2+ tometallic copper? (F = 96,500 coulombs/mol) (3%)(A) 2 (B) 48,250 (C) 96,500 (D) 193,000 (E) 386,000

6. What is the dominant form of triprotic acid at a pH of 6.50? (pK_a1=1.99, pK_a2=3.85,pK_a3=9.89) (3%)(A) H₂A^- (B) HA^2-(C) A^3- (D) HA^2- and H₂A^- are equal(E) A^3- and HA^2- are equal

7. What is the molar concentration of HNO₃ (63.0 g/mol) in a solution that has aspecific gravity of 1.42 and is 70.5% HNO₃ (w/w). (3%)(A) 11.2 M (B) 1.49 M(C) 0.79 M (D) 15.9 M(E) None of the above.