資訊推薦

• 18. An optical fiber has an index of refraction, n=1.5, and diameter, d = 10.0 um. It is surrounded
• 8.How many π bonds are present in the molecule shown?(A)0 (B)1 (C) 3(D)4
• 19. For a RLC circuit with L = 10 mH, C = 1.0 μF, and R = 200.0 Ω, when vs(t) = 2sin (10000t), what
• 9.Vildagliptin is a recently released antidiabetic drug (J. Med. Chem. 2010, 7902). How many element
• 20. A student performed Young's double-slit experiment in air using red light. When he immersed
• 10. Consider the reaction3A+B+C→D+Ewhere the rate law is defined as An experiment is carried out whe
• 10. In the structure below, the hybridization of the oxygen is ________ and the C-O-C bond angle is
• 11. The rate law for a reaction is found to be Rate = K[A]2[B]. Which of the following mechanisms gi
• 12. Which of the following statements is(are) true?I. An excited atom can return to its ground state
• 13. An electron in a one-dimensional box requires energy with wavelength 8080 nm to excite it from t
• 14. The energy expressions for the electrons in the Het ion and the hydrogen atom areEn(H)=-a\/n2 a
• 15. The wavelength of light associated with the n = 2 to n = 1 electron transition in the hydrogen s
• 11. The structure below is a potent analgesic agent (pain reliever) (J. Med. Chem., 2009, 5685). How
• 12. How many methylene groups are present in 2,4-dimethylhexane? (A)0 (B)1 (C) 2(D)6
• 13. Among the butane conformers, which occur at energy minima on a graph of potential energy versus
• 14. Which of the following species is not formed through a termination reaction in the chlorination
• 15. If the equilibrium constant (Keq) of a reaction is 0.5 then which of the following that must be
• 16. Which is a measure of the randomness of a system? (A)entropy (B)enthalpy (C) free energy(D)halog
• 17. Which of the following statements correctly describes the contribution of ΔS°toΔG°?(A)The entrop
• 18. Which of the following is true for the initiation step of a free radical chlorination reaction?
• 19. What term describes the structural relationship between cis-1,2-dimethylcyclopentane and trans-1
• 16. A strip of copper is placed in a 1 M solution of copper nitrate, and a strip of silver is placed
• 20. What is the structural relationship between the two molecule shown below?(A)constitutional isome
• 17. The standard potential for the reaction is 0.51 V. What is the equilibrium constant K for this r
• 21. How many asymmetric carbon atoms are present in the molecule shown?(A)0 (B)1 (C) 2(D)3