112年 - [無官方正解]112 國立嘉義大學_碩士班招生考試試題_應用化學系：分析化學#144356

1. What volume of a 36% HCl solution must be diluted to prepare 1.000 L of a 0.1000 M HCl solution? The density of 36% HCl is 1.18 g/mL. (The molecular mass of HCl is 36.45 g/mol.) (A) 11.7 mL (B) 8.6 mL (C) 1.2 mL (D) 10.1 mL (E) 64.6 mL

2. Which of the statements below are TRUE regarding the mean and standard deviation?
I As the number of measurements increases, \(\bar{x}\) approaches \(\mu\) if there is no random error.
II The square of the standard deviation is the average deviation.
III The mean is the center of the Gaussian distribution.
IV The standard deviation measures the width of the Gaussian distribution.
(A) II, III, and IV (B) I, III, and IV (C) I and II (D) I, II, and IV (E) III and IV

3. Any one of the mass spectrometers needs several essential components. They are I ion source II decelerator III detector IV mass separator V accelerator (A) I and IV (B) I, IV, and V (C) I, III, and IV (D) II, III, and IV (E) I, III, IV, and V

4. Which of the following statement is INCORRECT for gas chromatography detectors? (A) Thermal conductivity detectors respond to the thermal conductivity difference between analyte and carrier gas. (B) Thermal conductivity detectors respond to all analytes. (C) Flame ionization detectors generate signal by burning the analyte, generating electrons. (D) For thermal conductivity and flame ionization detectors, detector response is proportional to analyte concentration. (E) Flame ionization detectors are used only with inorganic compounds.

5. As particle size of packing material in a column decreases for HPLC, the required solvent pressure___________ , the plate number___________ , and the resolution ___________? (A) increases; increases; decreases (B) decreases; increases; increases (C) increases; decreases; decreases (D) increases; increases; increases (E) decreases; decreases; decreases

6. A set of five solutions are prepared by delivering 10 mL of unknown sample and increasing volumes of standard (0, 5, 10, 15, and 20 mL) into 50-mL volumetric flasks. Reagents are then added and diluted to volume. A plot of signals versus the final concentrations of standards is constructed. The x-intercept is −3.90 mM. What is the concentration of the unknown sample? (A) 0.39 mM (B) 3.9 mM (C) 19.5 mM (D) 39 mM (E) 195 mM

7. A Na₂CO₃standard solution is prepared by transferring4.9634 grams of primary standard- grade sodium carbonate to a 500.0-mL volumetric flask, dissolving the sample in ~100 mL of distilled deionized water and diluted to the mark. A 50.00-mL aliquot is taken and titrated with 85.30 mL of HCl solution. Calculate the concentration of the HCl solution. (The molecular mass of Na₂CO₃ is 105.99 g/mol.) (A) 0.0549 M (B) 0.1098 M (C) 0.1598 M (D) 0.1997 M (E) 0.3196 M