27. Which organic base is NOT found in RNA?
(A) Uracil
(B) Cytosine
(C) Thymine
(D) Adenine
(E) Guanine

23. The reaction system has already reached equilibrium. Which of the following statements is correct? (A) Additional H2O(g) added to the system will shift to the left to obtain the equilibrium. (B) As an exothermic reaction, the system will shift to the right to attain the equilibrium when temperature increases. (C) When carbon dioxide is removed, the system will shift to the left to achieve the equilibrium. (D) When volume of the reaction container is decreased, the system will shift to the right to reach the equilibrium. (E) Addition of helium gas into the reaction system will have no effects on its equilibrium.

24. Which elements are most similar in atomic size? (A) Li (Z = 3) and Na (Z = 11) (B) B (Z = 5) and Al (Z = 13) (C) Co (Z = 27) and Rh (Z = 45) (D) Zr (Z = 40) and Hf (Z = 72) (E) Be (Z = 4) and F (Z = 9)

25. In the Lewis structure of I3 – , there are _________ electrons around the central iodine atom. (A) 4 (B) 6 (C) 8 (D) 10 (E) 12

26. Which of the following statements is incorrect for colloids? (A) Colloids are suspension of very large particles ( ＞2000 nm) in a medium. (B) Tyndall effect is observed for colloids. (C) Electric repulsion seems to be the main factor that stabilizes colloids. (D) Removal of soot from smoke is an example of coagulation of colloids. (E) None of the above.

28. The figure below is a cross section of the electron probability distribution for an orbital. What are n and l values for this orbital? (A) n = 3, = 1 (B) n = 2,= 0 (C) n = 2, = 1 (D) n = 3, l = 2 (E) n = 2, = 2

29. A sample of a white solid is known to be NaHCO3, AgNO3, Na2S, or CaBr2. Which 0.1 M aqueous solution can be used to confirm the identity of the solid? (A) NH3(aq) (B) HCl(aq) (C) NaOH(aq) (D) KCl(aq) (E) CH3COOH(aq)

30. The Haber process _____________________ (A) is used to produce nitric acid. (B) is used to produce sulfuric acid. (C) is used to produce ammonia. (D) is used to produce urea. (E) None of the above.

61. Which of the following solution has shown the correct titration curve? (A) NH3 (B) CO32- (C) HCN (D) PO4 3- (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