60. The radioactive isotope  ²²⁶Ra decays to ²²² Rn with a half-life of 1600 years. The radioactive isotope  ²³⁸U decays to²³⁴ Th  with a half-life of 4.5× 10⁹ years. What is the ratio of the decay rate of 1 g  ²²⁶Ra to that of 10 g²³⁸ U  ?
(A) 3.0 × 10⁶
(B) 3.0 × 10^-7
(C) 3.0 × 10⁵
(D) 3.0 × 10^-6
(E) 3.0 × 10⁷

56. A series RLC circuit is connected to an ac source The resistance, capacitive reactance and inductive reactance are 40 Ω, 80 Ω, and 50 Ω respectively. What is the current () in the circuit? (A) 3.0 A (B) 0.040 A (C) 1.7 A (D) 1.4 A (E) 2.4 A

57. The rest mass of an electron isWhat is the kinetic energy of an electron with the speed of 0.80c? (The constant c is the speed of light in vacuum.) (A) (B) (C) (D) (E)

58. In the hydrogen spectrum, the ratio of the wavelengths for Lyman-α radiation (n = 2 to n = 1) to Balmer-α radiation (n = 3 to n = 2) is ______. (A)(B) (C) (D) 3 (E)

59. A sample of radioactive nuclei of a certain element can decay only by γ -emission and β -emission. If the half-life for γ -emission is 24 minutes and that for β -emission is 36 minutes, the half-life for the sample is (A) 30 minutes (B) 24 minutes (C) 20.8 minutes (D) 14.4 minutes (E) 6 minutes

61. Which of the following solution has shown the correct titration curve? (A) NH3 (B) CO3 2- (C) HCN (D) PO43- (E) NaOH

62. Cisplatin cis-[PtCl2(NH3)2] has been applied as an anti-tumor drug. What is its main interaction in vivo? (A) Binding with DNA. (B) Binding with lipid. (C) Binding with protein. (D) Binding with sugar. (E) Blocking ion absorption.

63. A chemist needs to prepare a buffered solution using one of the following acids (and its sodium salt): HA (Ka = 1.4 × 10-3 ), HB (Ka = 9.8 × 10-6 ), HC (Ka = 8.4 × 10-5 ), HD (Ka = 3.5 × 10-7 ), HE (Ka = 1.9 × 10-8 ). To prepare a solution buffered at pH = 5.10, which system will work best (a buffer with the best capacity)? (A) HA and its sodium salt (B) HB and its sodium salt (C) HC and its sodium salt (D) HD and its sodium salt (E) HE and its sodium salt

64. Of the following eleven compounds, how many of them have aromatic character? (A) 3 (B) 4 (C) 5 (D) 6 (E) 7

65. Which of the following species has the lowest dissociation energy? (A) O2 (B) O2 – (C) O2 2– (D) O2+ (E) O2 2+

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