資訊推薦

• 49. 有一電燈泡其規格標示為12V、60W，當頭燈點亮時用三用電錶量測其兩端直流電壓為12.8V， 則流過該頭燈之電流為何？ (A) 5.33A (B) 4.5A (C) 4.26A (D) 3.8
• 50. 單相三線式供電系統中，兩條火線間的電壓為何？ (A) 110V (B) 220V (C) 380V (D) 440V。
• 2. What is the correct formula for manganese (IV) oxide? (A) MnO4 (B) MnO3 (C) Mg2O3 (D) MnO2
• 3. The empirical formula of styrene is CH； its molar mass is 78.1. What is the molecular formula of
• 4. When the equation NH3 + O2 → NO + H2O is balanced with the smallest set of integers, the sum of t
• 5. In the following reaction, which species is the reducing agent?      (A) H+ (B) N in NO (C) C
• 6. How much water must be added to 20.0 mL of a 9.60 M sulfuric acid solution to make a 0.480 M solu
• 7. Consider three 1-L flasks at the same temperature and pressure. Flask A contains CO gas, flask B
• 8. Calculate the following ratio of effusion rate at T1 \/ Effusion rate at T2 for a gas at Kelvin
• 9. Calculate the temperature at which the average kinetic energy of O2 gas is twice that of He gas a
• 10. The reduction potentials for Au³+ and Ni2+ are as follows: (Hint: 96500 x 1.73 = 167,000)  Calcu
• 11. To decrease the value of K for the following exothermic reaction, we should  2A(g)+B(g) ⇌ 2C(g)
• 12. Calculate the pH of the M NaOH aqueous solutions at 25°C. (A) pH ≈ 2.0 (B) pH ≈ 12 (C) pH
• 13. At 25°C, given that the Ka for HA is 3.5 x 10⁻⁸, calculate the K value for the reaction of HA wi
• 14. Which of the following species is present in the greatest concentration in a 0.100 M H2SO4 solut
• 15. A 10-mL sample of tartaric acid () is titrated to a phenolphthalein endpoint with 20. mL of 1.0
• 16. How many different possible triethylbenzenes exist? (A) 6 (B) 5 (C) 4 (D) 3 (E) 2
• 17. When heat is added to proteins, the hydrogen bonding in the secondary structure breaks apart. Wh
• 18. A solution containing 10. mmol of and 5.0 mmol of is titrated with 1.0 M HCl. What volume of H
• 19. A radioactive isotope of vanadium, , decays by producing β particles and gamma rays. The nuclide
• 20. The number of a certain radioactive nuclide present in a sample decays from 2.41 x 10² to 6.02 x
• 21. Which of the following complexes shows geometric isomerism? (A) [Co(H2O)5Cl]SO4 (B) [Co(H2O)
• 22. How many unpaired electrons are there in the complex ion ? For this ion, the nitrate ligands pro
• 23. What ions are very important for the proper functioning of biologic systems, such as nerves and
• 24. What is the expected osmotic pressure, in torr, of a 0.0100 M solution of NaCl in water at 25°C?