2. Which one of the following statements about the structure of proteins is incorrect?
(A) Disulfide bonds provide strong intrachain interactions.
(B) Hydrogen bonding stabilizes the a-helix proteins.
(C) Heat can disrupt tertiary structure.
(D) Ionized amino acid side chains can form salt bridges within a protein.
(E) Nonpolar groups tend to face the outside of a protein in an aqueous solution.

38. The word “plummeting” in the second paragraph is closest in meaning to _______. (A) falling (B) soaring (C) moving (D) climbing

39. What does “that” refer to in the third paragraph? (A) A strong economy. (B) A social welfare system. (C) A steady supply of workers. (D) A growing population of the elderly.

40. Which of the following about Japan can be inferred from the passage? (A) Its population is growing faster due to higher childbirth rate. (B) The more elderly there are in a country, the better off the economy will be. (C) The longer people wait to get married, the better off Japan will be financially. (D) If the trend of later marriage continues, Japan will have a weaker economy.

1. What monomer(s) is(are) needed to make the polymer shown here?  Ⅰ. HOCH2CH2OHII. HOOCCH2CH2COOHIII. HOCH2CH2COOHIV. HOCH = CHOHV.HOOCCH =CHCOOH (A) II only (B) III only (C) I and II (D) IV and V (E) II and Ⅲ

3. Aspirin is formed vi____________ reaction. (A) combustion (B) condensation (C) addition (D) hydrogenation (E) substitution

4. For the process Co(NH3)5CI2+ + CI-→ Co(NH3)4Cl2+ + NH3, what would be the ratio of cis to trans isomers in the product? (A) 1:1 (B) 1:2 (C) 1:4 (D) 4:1 (E) 2:1

5. Which has the greater number of unpaired electrons?I. square planar Ni(CN)42-II. tetrahedral FeCl4- (A) I (B) II (C) Neither I nor II has any unpaired electrons. (D) Both I and II have the same (nonzero) number of unpaired electrons. (E) More information is needed.

6. You analyze for pyridine (K, is approximately 10-9) by dissolving 0.1000 g of the complex in 100 mL of H2O and titrating with a 0.01 M HCI solution. Which of the following indicators should be used to detect the endpoint? (Assume that the initial concentration of pyridine is approximately 0.01 M.) (A) bromophenol blue, pH range of color change = 3.0-4.6 (B) methyl red, pH range of color change = 4.8-6.0 (C) bromothymol blue, pH range of color change = 6.0-7.6 (D) thymol blue, pH range of color change = 8.0-9.6 (E) alizarin yellow, pH range of color change = 10.1-12.0

7. The deciding factor that makes HF a weak acid is that (A) F2 has a small bond energy. (B) HF has a large bond energy. (C) F- has the largest ionization energy of all the halide ions. (D) the enthalpy of hydration of F- is negative. (E) the entropy for hydration of F- is a large negative value.

8. Which of the following oxides is amphoteric? (A) BeO (B) MgO(C) CaO(D) SrO (E) BaO