4. Most chloride salts are soluble. Identify an exception to this generalization. a. FeCl2 b. CaCl2 c. MgCl2 d. PbCl2 e. BaCl2

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1 1. Balance the chemical equation associated with the complete combustion of benzene (C6H6) in oxygen. How many moles of oxygen will be required to completely combust a 0.96 mole sample of benzene? C6H6 + O2 CO2 + H2O a. 7.2 mole b. 14 mole c. 17 mole d. 12 mole e. 8.6 mole 2. If 15.0 mole of NH3 were reacted with 15.0 mole of NO, calculate the maximum amount of N2 that could be produced. 4 NH3 + 6 NO 5 N2 + 6 H2O a mole b mole c mole d mole e mole 3. If 15.0 mole of NH3 were reacted with 15.0 mole of NO. How much of the excess reactant will remain once the reaction is complete? a mole NO left unreacted b mole NH3 left unreacted c. 5.0 mole NO left unreacted d. 5.0 mole NH3 left unreacted e. 2.5 mole NO left unreacted 4 NH3 + 6 NO 5 N2 + 6 H2O 4. Most chloride salts are soluble. Identify an exception to this generalization. a. FeCl2 b. CaCl2 c. MgCl2 d. PbCl2 e. BaCl2 It s not that I m so smart, it s just that I stay with problems longer. ~ Albert Einstein Page 1 of 6

2 5. Select the precipitate that forms when aqueous lead(ii) nitrate is added to aqueous sodium sulfate. a. NaNO3 b. No precipitate forms c. Pb2SO4 d. PbS e. PbSO4 6. What are the spectator ions in the reaction (if any) that occurs when aqueous solutions of aluminum chloride and potassium perchlorate are combined and mixed? a. There are no spectator ions b. All the ions are spectator ions c. Aluminum and perchlorate ions d. Potassium ions and chloride ions e. Aluminum ions and potassium ions 7. How many grams of solute are in 1.75 L of M sodium monohydrogen phosphate (Na2HPO4) buffer solution? a. 114 grams b. 250 grams c. 139 grams d grams e. 444 grams 8. Which of the following solutions is most conductive? a. 1 M hydrochloric acid, HCl b. 1 M glucose, C6H12O6 c. 1 M acetic acid, HC2H3O2 d. 1 M methanol, CH3OH e. all these solutions would have the same conductivity 9. What volume of 0.26 M H2SO4 is needed to react completely with 50.0 ml of 0.48 M NaOH? a. 46 ml b. 67 ml c. 92 ml d. 67 ml e. 23 ml H2SO4 + 2NaOH Na2SO4 + 2H2O It s not that I m so smart, it s just that I stay with problems longer. ~ Albert Einstein Page 2 of 6

3 10. Which of the following compounds are non-electrolytes? NaOH HCl Na2SO4 H2CO3 C11H22O11 a. NaOH, HCl, and H2CO3 b. H2CO3 only c. H2CO3 and C11H22O11 only d. C11H22O11 only e. All are electrolytes, there are no non-electrolytes listed 11. The oxidation states of Cr in CrO2 - and CrO3 are and, respectively. a. 2, 3 b. 6, 2 c. 3, 6 d. 4, 6 e. 3,3 12. When the following redox reactions occurring in basic solution is balanced, there are molecules of water on the side of the equation. a. 7, reactant b. 5, product c. 5, reactant d. 2, product e. 2, reactant Cr2O7 2 + Cl Cr(OH)3 + Cl2 13. Which species functions as the oxidizing agent in the following reduction-oxidation reaction: a. Fe 2+ (aq) b. H + (aq) c. Mn 2+ (aq) d. MnO4 (aq) e. Fe 3+ (aq) 5 Fe 2+ (aq) + MnO4 (aq) + 8 H + (aq) Mn 2+ (aq) + 5 Fe 3+ (aq) + 4 H2O(l) 14. It takes 11.2 kj of energy to raise the temperature of 145 g of a substance from 25.0 C to 70.0 C. What is the specific heat of this substance? a J/g oc b J/g oc c J/g oc d J/g oc e J/g oc It s not that I m so smart, it s just that I stay with problems longer. ~ Albert Einstein Page 3 of 6

4 15. What is the final temperature of the system when a 30.0g iron ball at 70.0 o C is dropped into g water initially at a temperature of 25.0 o C? Specific heat capacity of Fe(s) = J/g o C and that of water is J/g o C. a o C b o C c o C d o C e o C 16. The major source of aluminum in the world is bauxite (mostly aluminum oxide). Its decomposition can be represented by the thermochemical equation given below. Is this reaction exothermic or endothermic 2 Al2O3(s) 4 Al(s) + 3 O2(g) Hrxn = 3352 kj a. Exothermic b. Endothermic 17. The major source of aluminum in the world is bauxite (mostly aluminum oxide). Its decomposition can be represented by the thermochemical equation given below. How many grams of aluminum can form when 555 kj of heat is involved? a. 160 grams b. 650 grams c grams d grams e grams 2 Al2O3(s) 4 Al(s) + 3 O2(g) Hrxn = 3352 kj 18. Silicon carbide, SiC, is an important industrial abrasive made by the high temperature reaction of SiO2 with carbon in the reaction given below. Calculate the standard heat of this reaction (as it is written) using the data given below. SiO2(s) + 3 C(s) SiC(s) + 2 CO2(g) a kj/mole b kj/mole c kj/mole d kj/mole 0 f H in kj/mole SiO2(s) SiC(s) 73.2 CO2(g) It s not that I m so smart, it s just that I stay with problems longer. ~ Albert Einstein Page 4 of 6

5 19. Two gaseous pollutants that form in auto exhausts are CO and NO. An environmental chemist is studying ways to convert them to less harmful gases through the following reaction. Use Hess s law and the information below to calculate H for the reaction: Target equation: CO(g) + NO(g) CO2(g) + ½N2(g) H =? Equation A: CO(g) + ½ O2(g) CO2(g) HA = kj Equation B: N2(g) + O2(g) 2NO(g) HB = kj a kj b kj c kj d kj e kj 20. What is the wavelength of light (in nm) emitted by a hydrogen atom when an electron moves from the n=5 to the n=2 level? a. 314 nm b. 304 nm c. 434 nm d. 586 nm e. 457 nm 21. Which of the following occurs only in discrete (quantized) increments? a. the speed a car drives on the interstate b. the number of eggs in a carton c. the altitude that an airplane flies d. the distance between two cities e. the mass of a steak 22. When atoms are excited by a flame, light of specific frequencies is emitted; this can best be explained by. a. Ground state electrons losing energy b. Electrons being expelled from the atom c. Electrons falling from high energy levels to lower ones d. Electrons falling into the nucleus e. Electrons moving from the ground state to excited states It s not that I m so smart, it s just that I stay with problems longer. ~ Albert Einstein Page 5 of 6

6 23. In physical terms the l quantum number of an atomic orbital determines a. Shape of the orbital, (i.e. the type of orbital) b. Orientation of the orbital is space c. Number of electrons the orbital can hold d. The electron shell of the orbital e. The spin of the electron 24. The following quantum numbers describe an electron in which subshell. n = 4, l = 1, ml = 1, s = ½ a. 4s b. 4d c. 3p d. 3d e. 4p 25. The energy of a photon of light is directly proportional to. a. The intensity of the light b. The frequency of the light c. Wavelength of the light d. Speed of the light e. Temperature 26. Which of the following orbital designations is incorrect? a. 4p b. 5f c. 5d d. 2d e. 7s It s not that I m so smart, it s just that I stay with problems longer. ~ Albert Einstein Page 6 of 6