11. A sample of N2 gas is contaminated with a gas ( A ) of unknown molar mass. The partial pressure of each gas is known to be 200. torr at 25°C. The gases are allowed to effuse through a pinhole, and it is found that gas A escapes at 2 times the rate of N2. The molar mass of gas A is:

(A) 7.00 g/mol

(B) 56 g/mol

(C) 14.01 g/mol

(D) 112 g/mol

(E) none of these

19. A sample of N2 gas is contaminated with a gas A of unknown molar mass. The partial pressure of each gas is known to be 200. torr at 25°C. The gases are allowed to effuse through a pinhole, and it is found that gas A escapes at 2 times the rate of N2. The molar mass of gas A is: (A)7.00 g/mol (B)56 g/mol (C)14.01 g/mol (D)112 g/mol (E)none of these

12. Chromium metal (52g/mol) crystallizes as a body-centered cubic lattice. If the atomic radius of Cr is 1.25 angstroms, what is the density of Cr metal in g/cm3? (Cr=52 g/mol) (A) 5.52 (B) 7.18 (C) 14.4 (D) 2.76 (E) 3.59

13. When one mole of benzene is vaporized at a constant pressure of 1.00 atm and at its boiling point of 353.0 K, 30.33 kJ of energy (heat) is absorbed and the volume change is +28.90 L. What is ΔH for this process? (1 L·atm = 101.3 J) (A) 27.40 kJ (B) 33.26 kJ (C) 1.43 kJ (D) 30.33 kJ (E) 59.23 kJ

14. A benzene-toluene solution is allowed to come to equilibrium with its vapor. The vapor is then condensed and found to contain 50.0 mole percent of each component. Calculate the composition (mole percent) of the original solution. The vapor pressures of pure benzene and toluene at this temperature are: 750. torr and 300. torr, respectively. (A) 50.2% benzene (B) 28.6% benzene (C) 71.0% benzene (D) 40.0% benzene (E) none of these

15. A 5.86-gram sample of a compound is dissolved in 250. grams of benzene. The freezing point of this solution is 1.02°C below that of pure benzene. What is the molar mass of this compound? (Note: Kf for benzene = 5.12°C/m.) Ignore significant figures for this problem. (A) 29.4 g/mol (B) 118 g/mol (C) 235 g/mol (D) 4.67 g/mol (E) 58.8 g/mol

16. A first-order reaction is 40.0% complete at the end of 28.7 minutes. What is the value of the rate constant (in min^-1)? (A) 3.19 x 10^-2 (B) 1.78 x 10^-2 (C) 56.2 (D) 31.3 (E) none of these

17. The rate constant k is dependent on I. the concentration of the reactant II. the nature of the reactants III. the temperature IV. the order of the reaction (A) none of these (B) one of these (C) two of these (D) three of these (E) all of these

18. Consider the following equilibrium: 2NOCl(g) ⇌ 2NO(g) + Cl2(g) with K = 1.6 x 10^-5. 1.00 mole of pure NOCl and 0.967 mole of pure Cl2 are placed in a 1.00-L container. Calculate the equilibrium concentration of Cl2(g). (A) 1.6 x 10^-5 M (B) 0.969 M (C) 0.485 M (D) 2.03 x 10^-3 M (E) 4.07 x 10^-3 M

19. Substance X has a heat of vaporization of 52.1 kJ/mol at its normal boiling point (423°C). For the process X(l) → X(g) at 1 atm and 423°C calculate the value of ΔS. (A) 0 (B) 74.9 J/K mol (C) 123 J/K mol (D) -74.9 J/K mol (E) -123 J/K mol

20. The following reaction has a ΔG° value of 48.71 kJ/mol at 25°C. HB(aq) + H2O(l) ⇌ H3O+(aq) + B-(aq) Calculate the Ka for the acid HB. (A) 0.981 (B) -19.7 (C) 2.89 x 10^-9 (D) 4.87 x 10^-5 (E) -234

115年 - [無官方正解]115 國立臺灣大學_轉學生招生考試：普通化學(C)#142702

115年 - 115 台灣聯合大學系統_學士班轉學生考試試題_A1：普通化學#142701

115年 - [無官方正解]115 台灣聯合大學系統_學士班轉學生考試試題_A6：普通化學#142699

115年 - [無官方正解]115 國立臺灣大學_轉學生招生考試：普通化學(A)#142644

114年 - 114 臺灣綜合大學系統_學士班轉學生考試試題:普通化學A#138275

114年 - 114 臺灣綜合大學系統_學士班轉學生考試試題:普通化學A#137946

114年 - 114 中國醫藥大學_學士班寒假轉學考試試題：普通化學（重複）#137262

114年 - 114 中國醫藥大學_學士班寒假轉學考試試題：普通化學#136734

114年 - 114 臺灣綜合大學系統_學士班轉學生聯合招生考試試題：普通化學Ａ#129359

114年 - [無官方正解]114 臺灣綜合大學系統_學士班轉學生聯合招生考試試題：普通化學Ｂ#129358