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• 21. Below is a phase diagram for compound X. You wish to purify a sample of X that was collected at
• 40. Which of the following oxidants will convert a primary alcohol to an aldehyde?1) sodium dichroma
• 22. Alkali halides commonly have either the sodium chloride structure or the cesium chloride structu
• 23. Liquid A has vapor pressure x. Liquid B has vapor pressure y, and x>y.What is the mole fracti
• 24. The oxidation states of P in KPF6 is: (A)+1 (B)+3 (C)+5 (D)-3 (E) -5
• 25. Which of the following compounds is the strongest acid? (A) Acetic acid (B) Chloric acid (C) Hyp
• 26. Which of the following ions has the lowest standard reduction potential? (A) Ag+ (B) Fe3+(C) Cr3
• 27. Which of the following names of ions is incorrect? (A) stannous: Sn2+ (B) plumbous: Pb2+ (C) fer
• 28. The density of compound XHn as gas is 2.393 times that of O2. If 0.01 mol of this compound react
• 29. Which of the following compound can be dissolved in water easily? (A) CsCl (B) AgCl (C) BaSO4 (D
• 30. Which of the following statements is correct? (A) NaF: acidic, cation acts as an acid )(B)NH4CI:
• 41. What are the relative integrations for the 1H NMR signals for the following compound?(A)3:1:2:2
• 31. Which of the following statements is correct for a mercury cell to produce chlorine and sodium h
• 42. If a molecule contains 4 elements of unsaturation and signals in the 1H NMR spectrum between δ
• 43. Using a 60 MHz spectrometer, the protons in dichloromethane appear at 5.30 ppm. When the same sa
• 44. Which of the following is another name for cyclobutadiene? (A)[2]annulene (B)[4]annulene (C) [6]
• 45. In electrophilic aromatic substitution reactions a bromine substituent ________. (A)is a deactiv
• 46. Which element is oxidized in the reaction below?Fe(CO)5 (l) + 2HI (g) → Fe(CO)4I2 (s) + CO (g) +
• 47. Which of the following reactions is a redox reaction?(a) K2CrO4 + BaCl2 → BaCrO4 + 2KCl(b) Pb22+
• 48. The purpose of the salt bridge in an electrochemical cell is to ________. (A)maintain electrical
• 49. Consider an electrochemical cell based on the reaction:2H+ (aq) + Sn (s) → Sn2+ (aq) + H2 (g) Wh
• 50. What is the cathode in an alkaline battery? (A)MnO2 (B)KOH (C) Zn powder(D)Mn2O3
• 51. The standard cell potential ( ) for the reaction below is +0.63 V. At 25 °C, the cell potential
• 32. About a chemical reaction, which of the following statements is correct? (A) the entropy change
• 33. Which of the following compounds is a paramagnetic substance? (A) N2 (B) NH3 (C) NO2 (D) hydrazi