113年 - 113 國立臺灣大學_轉學生招生考試：普通化學(C)#126296

選擇題 (24)

1. Shown to the right is a schematic diagram of a graduated cylinder. Here, what is the most appropriate reading of the liquid level?
(A) 15.6 mL (B) 15.62 mL (C) 15.685 mL (D) 15.69 mL (E) 15.7 mL

2. Which element has the highest second ionization energy (IE₂)? (A) Lithium (D) Carbon (B) Beryllium (E) Sodium (C) Boron

3. Regarding the compound shown to the right, which statement is NOT correct?
(A) It can function as a weak Brønsted base (B) All four atoms are located on the same plane (C) There exist other resonance structure(s) (D) Resonance structures transform between each other at a very fast rate (E) The three C-O bonds have the same bond length

4. If an alkane has the chemical formula C7H16, how many possible structural isomers exist? (A) 5 (B) 6 (C) 7 (D) 8 (E) 9

5. How many of the following compounds have optical isomers?
(A)0 (B) 1 (C) 2 (D) 3 (E) 4

6. Chlorobenzene and bromobenzene have similar structures and molecular dipole moments. Therefore, these two compounds can form an ideal solution. Given that the vapor pressures of pure chlorobenzene and bromobenzene at 25°C are = 8.8 Torr, = 4.2 Torr, respectively, calculate the molar fraction of bromobenzene in the vapor phase for a 1:4 chlorobenzene/bromobenzene solution. (A)0.20 (E) 0.86 (B) 0.34 (C) 0.66 (D) 0.80

7. When 1.32 g of benzoic acid (C₆H₅COOH) is dissolved in 12.52 g of benzene, the freezing point of the solution is determined to be 3.29°C. The normal freezing point of pure benzene is 5.50°C, and its molal freezing-point depression constant . Calculate the molar mass of benzoic acid by this colligative property method. (A) 61 g/mol (B) 110 g/mol (C) 122 g/mol (D) 220 g/mol (E) 244 g/mol

8. The thermal decomposition of PH3 into phosphorus and molecular hydrogen (4 PH₃ → P₄+6 H₂) is a first-order reaction. If the half-life of the reaction is 35.0 seconds at 680°C, calculate the time required for 90% of the original PH₃ to decompose. (A) 5.00 seconds (D) 116 seconds (B) 96.0 seconds (E) 173 seconds (C) 108 seconds

9. Water gas is a poisonous, flammable gas mixture comprising carbon monoxide (CO) and hydrogen (H₂). It can be produced by blowing water vapor over red-hot coal:

Which of the following statements is correct? (A) The reaction is spontaneous below a certain temperature (B) The reaction is spontaneous above a certain temperature (C) The reaction is always spontaneous (D) The reaction is always non-spontaneous (E) The reaction is always at equilibrium

10. Based on the table below, determine the equilibrium constant K and the reaction enthalpy ΔH for the reaction A+B+2D ⇌ 2E.

(A)K = K₁/K₂, ΔH – ΔH₁ – ΔH₂ (B) K = K₁/K₂², ΔH – ΔH₁ + 2ΔH₂ (C) K = K₁ - K₂, ΔH = ΔH₁ – 2ΔH₂ (D) K = K₁/K₂², ΔH – ΔH₁ – 2ΔH₂ (E) K = K₁-2K₂, ΔH – ΔH₁ – 2ΔH₂

11. The equilibrium constant Kp = 110 for the following reaction at 400°C:

H₂(g) + I₂(g) ⇌2 HI(g)

= 2 bar, which direction will this reaction go? (A) The reaction goes toward products because Q＜K (B) The reaction goes toward products because Q＞K (C) The reaction goes toward reactants because Q＜K (D) The reaction goes toward reactants because Q＞K (E) The reaction does not move because the system is already at an equilibrium

12. Phosphoric acid (H₃PO₄) is a triprotic acid with Calculate the concentration of in a 5.0 M H₃PO₄ solution. (A)(B)(C)(D)(E)

13. Potassium ferricyanide, K₃[Fe(CN)₆], exhibits a bright red color and can be used for developing photographic films. What is the oxidation state and the number of d electrons of Fe in this compound? (A) ; 5 d electrons (D) ; 6 d electrons (B) ; 3 d electrons (E) ; 4 d electrons (C) ; 6 d electrons

14. Continuing the previous question, how many unpaired d electrons are on iron if cyanide is a strong-field ligand? (A)0 (C) 2 (B) 1 (D) 3 (E) 4

15. Which following atomic orbital has the highest number of radial nodes? (A) 1s (B) 2p (C) 3s (D) 3p (E) 4d

16. According to quantum mechanics, all properties of a particle confined in a one-dimensional space (coordinate x) can be derived from its wavefunction ψ(x). Which of the following quantities informs the probability density of finding the particle at position x₀? (A)ψ(x₀) (B) |ψ(x₀)|² (C) (D) (E) None of the above

17. If λ₁ is the wavelength required to excite an electron in H from 2s to 4p level, what is the wavelength emitted by the same electron when relaxing from 4p back to 1s level? (A)λ₁/5 (B)λ₁/4 (C) λ₁/2 (D) 2λ₁ (Ε) 5λ₁

18. Photodissociation of chlorine molecules (Cl₂ + light 2 Cl‧) creates highly reactive chlorine radicals, which play important roles in chlorination of hydrocarbons, polymerization, and catalyzing the ozone decomposition reaction. According to the molecular orbital theory, what is the lowest-energy excitation pathway (initial MO → final MO) that causes a ground-state Cl₂ molecule to dissociate? (Assuming the MO's have higher energy than the MO.) (A) (B)(C) (D) (Ε)

19. Which statement below is NOT correct? (A)Redox reactions with a positive △G⁰ would have a negative electromotive force (B) The electromotive force reaches a maximum value when the redox reaction is at equilibrium (C) The cell voltage of a galvanic cell may change with the ion concentrations in the cell (D) Electrolytic cells use electric energy to force non-spontaneous redox reactions to occur (E) The electromotive force of a galvanic cell is an intensive property

20. Shown to the right is a reaction coordinate diagram of an elementary reaction. Select the correct statement.
(A) If the temperature is increased, k₁ will increase, and will decrease (B)k1 ＞ because the forward reaction has a higher activation energy (C) If the temperature is increased, k₁ will decrease, and will increase (D)k₁ = when the system reaches equilibrium (E) The equilibrium constant K = k₁/

複選題

21. Choose the salt(s) that, when dissolved in water, has pH ＜ 7 at 25°C. (A)KCI (B) NH₄Cl (C) Fe(NO₃)₃ (D) NaNO₃ (E) NaNO₂

複選題

22. The titration curves for two acids (I and II, same sample volume) using the same standardized NaOH solution are shown to the right. Select all correct descriptions regarding the comparison between two acids.
(A) Acid I is the stronger acid (B) Acid I has a higher original concentration than acid II (C) Both acids are monoprotic (D) Acid II can be used to prepare a buffer solution I pH II (E) When acid II is titrated to the equivalence point at 25°C, the pH of the solution would be larger than 7

複選題

23. What does Maxwell-Boltzmann distribution of molecular speeds inform? Volume of NaOH added (mL) (A) Through collision with each other, all gas molecules reach the same speed at thermal equilibrium (B) For the same molecule, its root mean square (r.m.s.) speed increases with increasing temperature (C) At the same temperature, lighter molecules would have higher r.m.s. speed (D)P（E）, the probability of a molecule possessing a certain kinetic energy E, always decreases with E (E) Individual gas molecules do not have the same kinetic energy

複選題

24. Which of the following molecule(s) is or are polar? (B) BeF₂ (C) C₂H₄ (A) SO₂ (D) H₂S (E) 13

申論題 (2)

25. The molar solubility of Pb(IO₃)₂ in a 0.10 M NaIOs solution is 2.4 × at 25°C.

(25A, 2%) Calculate the solubility product constant of Pb(IO₃)₂.

(25B, ) Calculate the molar solubility of Pb(IO₃)₂ in pure water.

(25C, ) Calculate the standard Gibbs free energy change (△G) for the dissolution of Pb(IO₃)₂ in H2O.

(25D, ) Calculate when a chemical equilibrium is reached after mixing 20.0 mL of0.10 M NaIO₃ with 20.0 mL of 0.025 M Pb(NO₃)₂.

26. Redox chemistry

(26A, 5%) Balance the following redox reaction under acidic conditions and indicate the oxidizing agent and the reducing agent: (1)

(26B, 2%) Write down the expression of the equilibrium constant K. for reaction (1) after balancing.

(26C, 3%) The reaction (1) after balancing has a standard electromotive force (E⁰) of 0.56V. Calculate the value of the equilibrium constant K. at 25°C.

Planck constant h = 6.62608 x J s