70. Please balance the following equation (o, p, q, x, y, z are reaction coefficients). What is the sum of all coefficients (o + p + q + x + y + z) ?
(A) 18
(B) 20
(C) 22
(D) 24
(E) 26

66. According to the Bohr Model, please use the equation below and calculate the minimum energy required to remove the electron from a He+ ion in its first excited state. (A) 2.178 x 10-18 J (B) 5.445 x 10-19 J (C) 8.712 x 10-18 J (D) 4.356 x 10-18 J (E) 1.089 x 10-18 J

67. About the atomic orbitals, which of the following statements is incorrect? (A) In a polyelectronic atom, the orbital relative energies are E3s ＜ E3p ＜ E3d. (B) In H atom, energy is absorbed and electron jumps from 1s to 3s orbital. (C) The 2p orbital is spherically symmetric. (D) The square of the wave function is indicated as a probability distribution. (E) None of the above.

複選題68. NF3 has a bond angle of 102.5º, while PF3 has a bond angle of 96.3º. What is the best explanation for the larger bond angle in NF3? (A) The nitrogen 2s orbital participates more in bonding than the phosphorus 3s orbital does. (B) Nitrogen is more electronegative than phosphorus. (C) NF3 has no unpaired electrons while PF3 has two unpaired electrons. (D) NF3 is an ionic compound while PF3 forms covalent bonds. (E) NF3 adopts a trigonal geometry, while PF3 displays a trigonal planar configuration.

69. When the reaction below is at equilibrium, what is the temperature? 2 NO(g) + O2(g) → 2 NO2(g) H   rxn = –113 kJ•mol–1 S°rxn = –145 J•mol–1 •K–1 (A) –195 °C (B) 77.9 °C (C) 350.9 °C (D) 506 °C (E) 779 °C

71. For the reaction A + B  products, the following data were obtained: What is the experimental rate law? (A) Rate = k[A] (B) Rate = k[B] (C) Rate = k[A][B] (D) Rate = k[A]2 [B] (E) Rate = k[A][B]2 

72. In the blood of an adult human, there are approximately 2.64 ✖ 1013 red blood cells with a total of 2.90 g of iron. On the average, how many iron atoms in each red blood cell? (Fe = 55.85 g/mol) (A) 5.19 ✖  10–2 (B) 4.72 ✖ 1011 (C) 1.09 ✖  10–13 (D) 9.10 ✖  1012 (E) 1.18 ✖  109

73. What is the rate constant for radioactive decay of 14CO2(g) at 0.1 atm? (The half-life of C-14 nucleus is 5730 years.) (A) 1.38 × 10‒8 h ‒1 (B) 2.76 × 10‒8 h ‒1 (C) 1.38 × 10‒9 h ‒1 (D) 3.45 × 10‒9 h ‒1 (E) 6.90 × 10‒9 h ‒1

74. 1 mg of a non-electrolyte protein is dissolved in enough water to make 1.00 mL of solution. The osmotic pressure of the solution is found to be 1.56 torr at 25ºC. The molecular weight of this protein is approximately ________ g. (A) 1.19 × 107 (B) 11905 (C) 5950 (D) 999 (E) None of the above

75. When the permanganate ion, MnO4ˉ, acts as an oxidizing agent which forms different products depending on the pH of the solution. Which species corresponding to the conditions listed below is correct? (A) A (B) B (C) C (D) D (E) E

76. Alanine, H2NCH(CH3)CO2H, has Ka = 4.5 × 10–3 and Kb = 7.4 × 10–5 . Which species has the highest concentration in water (pH=7.0)? (A) H2NCH(CH3)CO2H (B) +H3NCH(CH3)CO2H (C) H2NCH(CH3)CO2 – (D) H2NCH(CH3)CO2H2 + (E) +H3NCH(CH3)CO2 –