13. Which quantity of nickel has the largest mass? (A) one mole (B) 6.02 x 1023atoms (C) 58.7 grams (D) 22.4 moles 14. Which element should have properties most like those of phosphorus? 15. Which of the following isoelectronic ions should have the smalles ionic radius? 16. Which element has no known stable chemical compounds?
17. For which pair of atoms is the electronegativity difference the greatest? (A) B, C (B) Li, I (C) K, Cl (D) Se, S 18. In which molecule would you find a triple covalent bond? 19. How many unpaired electrons are found in the most stable electronic state of a sulfur atom? 20. The arrangement of the atoms in the ammonia molecule at its lowest energy is described as 21. The most reasonable Lewis structure for the HNO2molecule is 22. In which electronic state would a hydrogen atom be able to absorb a photon of elctromagnetic radiation but not be able to emit a photon? (A) 1s1(B) 2s1(C) 3p 1 (D) 4d 1
23. Which molecule is non-polar? 24. Which compound is most likely to be ionic? 25. The very high heat of vaporization of H2O is mainly a result of 26. A standard solution of 0.154 M HCl is used to determine the concentration of a NaOH solution whose concentration is unknown. If 33.5 mL of the acid solution are required to neutralize 25.0 mL of the base solution, the concentration of the NaOH in moles/liter is (A) 25.0 / (0.154)(33.5) (B) (0.154)(25.0) / 33.5 (C) (33.5 + 25.0) / 0.514 (D) (0.514)(33.5) / 25.0 27. A species which acts as an acid according to the Bronsted model of acids and bases is 28. The hydrogen ion concentration corresponding to a pH of 8.64 is 29. Consider a 1.0 M solution of each of the following salts. Which will have the lowest freezing point?
30. Which has the greatest molar solubility in water at 25°C? (A) ammonium nitrate (B) calcium sulfate (C) copper (II) sulfide (D) silver carbonate 31. The heat of combustion of CH4is 882 kJ/mole. How much heat would be liberated by the complete combustion of 4.00 g of CH4? 32. Which process is exothermic?