Chemistry 1 Final Exam Study Guide Spring 2009 1. If a substance has a mass of 36.4 g and a volume of 8.500 ml, what is its density? 2. Which involves a chemical change? a. powdering sugar b. condensing steam c. magnetizing an iron bar d. separating cream from milk e. exposing photographic film to light 3. Describe the following separation techniques. a. filtration b. distillation c. chromatography 4. During an experiment, a student found the concentration of an aqueous sucrose solution to be 2.368 M. If the actual concentration of the solution is 2.450 M, what is the student s percent error? 5. Complete the following chart for the 6 phase changes. Phase Change Initial Phase Final Phase Vaporization Sublimation Freezing Deposition Melting Condensation Endothermic or Exothermic?
6. How do atmospheric pressure and the vapor pressure of a substance relate to the boiling point of the substance? 7. What is correct formula for nickel (II) nitrate? a. NiNO 2 b. Ni(NO) 3 c. Ni 2 NO 3 d. Ni(NO 3 ) 2 8. How many liters of methane gas (CH 4 ) at STP are there in 3.67 x 10 24 molecules? a. 58.7 L b. 137 L c. 97.5 L d. 218 L 9. Name the following compound: FeSO 4 6H 2 O. What is its molar mass? 10. If you have one mole samples of silver (Ag), gold (Au), and platinum (Pt), which quantity will be the same for all of the samples? a. volume b. density c. monetary value of metals d. number of atoms e. mass 11. What is the percent by mass of magnesium in magnesium chloride? a. 68.5% b. 34.2% c. 25.5% d. 50.0% 12. Write a balanced equation for a reaction between NaOH and CuCl 2.
13. Balance the following equation: Ca(OH) 2 + H 3 PO 4 Ca 3 (PO 4 ) 2 + H 2 O 14. Calculate the mass of CO 2 formed from the combustion of 25 grams of methane: CH 4 + 2O 2 CO 2 + 2H 2 O 15. Citric acid (H 3 C 6 H 5 O 7 ) is a product of the fermentation of sucrose (C 12 H 22 O 11 ) in air. C 12 H 22 O 11 + 3 O 2 2 H 3 C 6 H 5 O 7 + 3 H 2 O Determine the number of moles of citric acid produced when 2.50 moles of sucrose reacts. 16. One mole of gas has volume of 17.0 liters at 743 mm Hg pressure. What will the volume be if the pressure is doubled and the moles of gas are doubled while the temperature is held constant. a. 34.0 L b. 17.0 L c. 8.5 L d. 22.4L 17. A 5 gram sample of ethanol required 28.2 kj of energy to be heated from 21ºC to 53ºC. What is the specific heat of ethanol? 18. A 60.0 ml sample of oxygen gas is collected over water at 25.0 C. The total pressure inside the tube is 785.0 mm Hg. The vapor pressure of water at 25.0 C is 23.8 mm Hg. What is the pressure of the oxygen gas?
19. What is the empirical formula of a compound that is 59.37% lead and 40.73% chlorine? a. PbCl b. PbCl 2 c. Pb 2 Cl 3 d. PbCl 4 20. Determine the heat of reaction, H, for the combustion of propane. C 3 H 8 + 5O 2 3CO 2 + 4H 2 O Substance Propane Oxygen Carbon Dioxide Water Heat of Formation -104 kj/mole 0 kj/mole -393.5 kj/mole -285.8 kj/mole 21. What is the number of protons in the isotope of copper,? a. 67 b. 96 c. 29 d. 38 22. Which chemical family on the periodic table has an outer (valence) shell with the electron configuration, s 2 p 5? a. Halogens b. Alkali metals c. Noble gases d.alkaline earth metals 23. Energy is released in the form of light when an electron changes from a ( higher or lower) energy level. 24. Sketch an endothermic energy diagram labeling: Reactants, Products, Activation Energy
25. Give four explanations as to how a catalyst speeds up a chemical reaction. Which one is the best? 26. The balanced chemical equation for the reaction of hydrobromic acid and oxygen gas to form water and bromine gas is 4HBr + O 2 2H 2 O + 2Br 2. In the following mechanism for the reaction, underline the rate determining step and circle any intermediates. HBr + O 2 HOOBr HOOBr + HBr 2HOBr HOBr + HBr H 2 O + Br 2 HOBr + HBr H 2 O + Br 2 4HBr + O 2 2H 2 O + 2Br 2 slow fast fast fast 27. Write the equilibrium expression for the following reaction: 2 A (g) + 3 B ( l) 2 C (s) + 3 D 28. Which substance is miscible with ethene, a nonpolar solvent? a. water, H 2 O b. potassium chloride, KCl c. Ethanol, C 2 H 5 OH d. Carbon tetrachloride, CCl 4 29. Explain the periodic trend in boiling point, electronegativity, electron affinity and first ionization energy for the halogens.
30. What is the molecular geometry around the central atom in AlCl 3? a. linear b. tetrahedral c. trigonal planar d. trigonal pyramidal 31. Which compound contains both ionic and covalent bonds? a. KCl b. NH 4 Cl c. CCl 4 d. CO 2 32. Determine what type of decay occurs when thorium-231 undergoes radioactive decay to form protactinium-231. 33. How many milliliters of a 12 M HNO 3 stock solution should be added to distilled water to prepare 2.5 L of a 1.0 M solution? 34. Consider the following equation: PbCrO 4 (s) Pb 2+ (aq) + CrO 4 2- (aq). The solution and solid are in equilibrium. What would happen to the solubility of PbCrO 4 if a solution of PbNO 3 were added to the saturated PbCrO 4 solution? 35. Identify the conjugate acid-base pairs in the following equation. HNO 2 + H 2 O NO 2 - + H 3 O + 36. What is the concentration of a household ammonia cleaning solution if 49.90 ml 0.5900M HCl is required to neutralize 25.00 ml of solution? 37. Calculate the ph of 0.050M HNO 3.
38. Determine the oxidation number of each element in Cu(NO 3 ) 2. 39. Draw the general structure for a carboxylic acid. 40. When a solute is added to a pure solvent the freezing point of the solvent will and the boiling point of the solvent will. 41. Calculate the molar mass of magnesium chlorate, Mg(ClO 3 ) 2. 42. Write a balanced equation for the complete combustion of ethane, C 2 H 6. 43. As the temperature of a liquid rises, will the vapor pressure of the liquid increase or decrease? 44. Use significant figures to determine the volume in ml of an object with the following dimensions: length = 3.15 cm width = 2.4 cm height = 1.25 cm 45. The density of a substance is 3.75 g/ml. Determine the mass of the substance in grams if the volume measures 7.50 ml. 46. Calculate the volume in liters for 50.0 grams of nitrogen gas at STP.
47. Which of the following measurements contains the fewest number of atoms? a. 7.0 g of magnesium b. 7.0 g of zinc c. 7.0 g of silver d. 7.0 g of gold 48. Using the precision of the graduated cylinder pictures below, what is the measured volume in ml? a. 14 ml b. 13.5 ml c. 13 ml d. 14.5 ml 49. What phase change occurs as pressure rises from 0.0 atm to 1.0 atm in the following phase diagram? a. deposition b. boiling c. melting d. sublimation 50. Which mixture is heterogeneous? a. salt water b. vinegar c. blood d. air 51. What group (X) on the periodic table would form X 3 (PO 4 ) 2?
52. What is the total number of atoms in (C 2 H 3 O 2 ) 2 SO 4? 53. A sample of gas at STP has a volume of 200 ml. What would the volume be at a temperature of 87ºC and a pressure of 952 mmhg? 54. Find the pressure of 6.5 g of neon at 50ºC in a 2L container. 55. Calculate the percent by mass of water in this hydrate: CuSO 4 5H 2 O 56. What is the molecular formula of styrene if its empirical formula is CH and its molar mass is 104 g/mol? 57. Calculate the mass of CO 2 formed from the combustion of 3.2 liters of methane: CH 4 + 2O 2 CO 2 + 2H 2 O 58. If 5 moles of oxygen is added to 5 moles of hydrogen, water will quickly form. Determine how much water, oxygen, and hydrogen will be present after the reaction.
59. What mass of ethanol must be burned in order to liberate 53.40 kj of heat? C 2 H 5 OH + 3 O 2 2 CO 2 + 3 H 2 O ΔH = 1257 kj 60. Which of the following describe combustion reactions: a) They are endothermic b) They release heat c) Entropy decreases d) Enthalpy increases 61. If a chemical reaction takes several steps to occur, the speed and rate of reaction depends on: a. the fastest step. b. the slowest step c. the total of all of the steps d. the equilibrium constant 62. A B Assume that the potential energy reflects the enthalpy(h) in kj/mol. A) Which of the above two reactions is exothermic? B) In which of the above reactions is the enthalpy of the products greater than that of the reactants? C) What is the activation energy (kj/mol) for reaction A? reaction B? D) What is the enthalpy change (ΔH) in reaction A? reaction B?
63. This equation below.shows the reaction for the equilibrium reaction called the Haber process. Write the equilibrium constant expression for the Haber process. 64. A) What periodic trend in period 1, 2, 3, and 4 elements does this graph represent? a. atomic radius b. ionic radius c. electron affinity d. first ionization energy B) What periodic trend in alkali earth metals does this graph represent? a. atomic radius b. ionic radius c. electron affinity d. first ionization energy
C) What periodic trend in period 3 elements does this graph represent? a. atomic radius b. ionic radius c. electron affinity d. first ionization energy 65. Which of these are isotopes of one another? a. Ca and Ca +2 b. Ca +2 and O -2 c. uranium-235 and uranium-238 d. carbon-14 and uranium-238 66. Isotopes of an element vary in the number of. Ions of an element like iron vary in the number of. a. protons; neutrons d. electrons; neutrons b. neutrons; protons e. protons; electrons c. neutrons; electrons f. electrons; protons 67. Which element has chemical properties most similar to sulfur? a. phosphorus b. chlorine c. argon d. nitrogen e. bismuth 68. A) Which best represents the electron configuration for titanium in the ground state? a. [Ar] 3s2 3d2 b. [Ar] 3s2 3d2 c. [Ar] 4s2 4d2 d. [Ar] 4s2 3d2 B) Which best represents the d-orbital electron distribution for rhodium (Z=45)? a. 4d b. 4d c. 4d d. 4d
69. Determine which of the following compounds fits each of the descriptions below: [Hint: Draw Lewis dot structures first.] CO 2 H 2 O Cl 2 CCl 4 Polar molecule with polar covalent bonds. Nonpolar molecule with nonpolar covalent bonding. Nonpolar molecule with double polar covalent bonds. Nonpolar molecule with single polar covalent bonds. 70. Electrolytes are compounds that, when dissolved in water, enable the solution to conduct electrical current. Electrolytes are able to form ions in aqueous solution. Which of these is NOT an electrolyte? a. sulfuric acid b. sodium hydroxide c. glucose d. calcium chloride 71. Which substance will have the lowest boiling point? a. C 2 H 5 OH b. C 4 H 9 OH c. C 6 H 13 OH d. C 8 H 17 OH 72. A 20.0 gram sample of thorium-234 has a half life of 25 days. What percent of the original sample will remain after 125 days? 73. Which of the following organic hydrocarbons contains a triple bond? a. C 2 H 4 b. C 3 H 8 c. C 4 H 6 d. C 6 H 6 74. Circle the answers that correctly complete the following statement. (High / Low) temperature and (high / low) pressure conditions give you the greatest solubility of a gas in water.
75. What factor has the biggest effect on the solubility of a solid solute in water: surface area, temperature or atmospheric pressure? 76. Give the conjugate acid and conjugate base for hydrogen sulfate ion, HSO 4 -. Conjugate Acid Conjugate Base 77. Rank the following Bronsted-Lowry acids from weakest to strongest. H 2 C 2 O 4, K a =5.9 x 10-2 H2CO3, K a =4.2 x 10-7 HC 2 H 3 O 2, K a =1.8 x 10-5 78. What is the concentration of hydrogen ion, [H + ], in a.0125 M solution of potassium hydroxide, KOH? Calculate the ph and the poh for this solution. 79. Circle the answers that correctly complete the following statement. A 16.0 M solution of sulfuric acid, H 2 SO 4, could be described as (dilute / concentrated) and a (weak / strong) electrolyte. 80. Complete the following statements about voltaic cells. A) Oxidation takes place at the. B) Reduction takes place at the. C) Electrons flow from the to the.