2. If a gas is released in a reaction (ex: Hydrogen gas bubbles off), is it written as a reactant or a product?

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1 PRE-AP CHEMISTRY SPRING FINAL EXAM REVIEW Name _ Period Exam Date 100% COMPLETION OF THIS REVIEW BY THE DAY OF YOUR FINAL EXAM WILL COUNT AS A 5 POINT BONUS ADDED TO YOUR FINAL EXAM SCORE. THERE WILL BE NO OTHE R ADJUSTMENT ON THE EXAM. IT IS DUE WHEN YOU CO ME TO TAKE YOUR EXAM. GOOD LUCK! 1. What is a precipitate? 2. If a gas is released in a reaction (ex: Hydrogen gas bubbles off), is it written as a reactant or a product? 3. What is the difference between a subscript and a coefficient? Which do we change to balance a compound formula, and which do we change to balance a reaction? 4. What does the Law of Conservation of Mass tell us? 5. How many of each type of atom are in each of the following? Also, determine how many total atoms are in the compound. a. ammonium carbonate b. calcium phosphate 6. What is the general formula for the following types of reactions? a. Synthesis b. Decomposition c. Single Replacement d. Double Replacement e. Combustion 7. For each of the following reactions, identify the type of reaction (synthesis, decomposition, single replacement, double replacement, or combustion) and balance using coefficients. Type of Reaction Balance NH 4NO 2 N 2 + H 2O Fe 3O 4 + Al Al 2O 3 + Fe C 10H 20 + O 2 CO 2 + H 2O H 3PO 4 + Mg(OH) 2 Mg 3(PO 4) 2 + H 2O Na + O 2 Na 2O

2 8. For each of the following reactions, identify the type of reaction and predict the products. Then, balance using coefficients. Assume all reactions occur. Type of Reaction Balance Cl 2 + KBr Ca + Cl 2 H 2O C 3H 7OH + O 2 K + CuSO 4 9. Find the molar mass of Ca(ClO 3) 2. You must show work to get credit. (Ans g/mol) 10. Find the molar mass of (NH 4) 2SO 4 You must show work to get credit. (Ans g/mol) 11. Determine the mass of moles of NH 3. You must show work to get credit. (Ans g NH 3) 12. Calculate the mass of molecules of H 2. You must show work to get credit. (Ans g H 2) 13. Calculate the amount in moles of molecules of H 2S. You must show work to get credit. (Ans mol H 2S) 14. Calculate the percent composition of sucrose (C 12H 22O 11). You must show work to get credit. (Ans. 42.1% C, 6.5% H, 51.4 % O) 15. Calculate the percent composition of Aluminum Sulfate. You must show work to get credit. (Ans. 15.8% Al, 28.1% S, 56.1% O) 16. Find the empirical formula for a compound which contains 32.8% chromium and 67.2% chlorine. You must show work to get credit. (Ans. CrCl 3)

3 17. What is the molecular formula of cyanuric chloride if the empirical formula is CClN and the molecular mass is known to be g/mole? You must show work to get credit. (Ans. C 3Cl 3N 3) 18. What is the difference between an actual yield and a theoretical yield? 19. What is a limiting reactant? 20. How many moles of O 2 are required to produce 100. grams of H 2O in a synthesis reaction in which there is excess H 2? You must show work to get credit. (Ans mol O 2) 2 H 2 + O 2 2 H 2O 21. How many molecules of O 2 are required for the complete combustion of 23.0 g of C 6H 14? You must show work to get credit. (Ans mlcl O 2) 2 C 6H O 2 12 CO H 2O 22. How many grams of ammonia (NH 3) can theoretically be produced by the synthesis of excess hydrogen gas and 235 grams of nitrogen gas in a synthesis reaction? You must show work to get credit. (Ans. 286 g) 23. How many liters of hydrogen chloride gas could theoretically be produced at STP by reacting 34.7 liters of hydrogen gas at STP with excess chlorine gas? You must show work to get credit. (Ans L) 24. If only 60.0 Liters of HCl gas were actually produced in the previous problem, what s the percent yield? You must show work to get credit. (Ans. 86.5%)

4 25. What is STP? What are the values of STP? 26. Temperature is a measure of what? 27. What unit for temperature must be used in all gas law calculations? 28. State Boyle s Law. Show the formula. Sketch a graph. Is this a direct or indirect relationship? 29. State Charles s Law. Show the formula. Sketch a graph. Is this a direct or indirect relationship? 30. State Gay-Lussac s Law. Show the formula. Sketch a graph. Is this a direct or indirect relationship? 31. Give the formula for the combined gas law. 32. Give the formula for the ideal gas law. Also, state what each symbol stands for, and what units must be used for T and V. 33. What formula is used to change Celsius to Kelvin? 34. Which pressure (high or low) and which temperature (high or low) would gas molecules have the greatest Kinetic Energy? 35. If the pressure of a gas is 1.30 atm at 45.5 o C under constant volume and the temperature decreases to 15.3 o C, what does the pressure change to? You must show work to get credit. (Ans atm) 36. If a sample of gas has a volume of 100. ml when the pressure is 150. kpa, what will be the volume of the gas in ml at 930 torr if the temperature also changes from 10.0 C to 5.00 C? You must show work to get credit. (Ans. 119 ml) 37. A 1.00 liter mixture of gas is produced by mixing nitrogen and oxygen. If the pressure of the nitrogen alone is known to be 455 torr and the pressure of the oxygen alone is known to be 79.0 kpa, what is the total pressure of the gas mixture in the flask in kpa? You must show work to get credit. (Ans kpa)

5 38. If 1.17 grams of helium are put into a 5.00 liter container at 10 o C, what would be the pressure in the container (in torrs)? You must show work to get credit. (Ans torr) 39. What would be the density of oxygen gas as 70ºC and 3.0 atm pressure? You must show work to get credit. (Ans. 3.4 g/l) 40. If the density of a gas is known to be 1.96 g/l at 755 torr and 5ºC, what is the molar mass of the gas? You must show work to get credit. (Ans g/mol) 41. Explain why water is a polar molecule. 42. Define: a. Solvent b. Solute c. Saturated d. Unsaturated e. Supersaturated f. Concentration g. Dilution h. Soluble i. Miscible j. Immiscible 43. Define electrolyte. What two requirements are necessary for a substance to be an electrolyte?

6 44. Tell whether the following would be an electrolyte or not: a. NaOH b. HCl c. CH 4 d. CaSO 4 e. HC 2H 3O 2 f. C 6H 13OH 45. What is the rule for solubility of covalent compounds? 46. Use a solubility chart to tell whether the following ionic compounds are soluble in water or not. Put the correct state symbol (s) or (aq) next to the substance. a. Ammonium carbonate b. Barium sulfate c. Magnesium nitrate d. Mercury (I) acetate e. Copper (II) sulfite 47. What is another word that can be used to describe a homogeneous mixture? 48. Under which conditions are gases most soluble in water? (High or low temperature / high or low pressure) 49. Write the following: a. Factors which increase the rate of dissolving of solid solutes b. Factors which increase the amount of dissolving of solid solutes c. Factors which increase the amount of dissolving of gaseous solutes 50. In a saturated solution, if more solute is added, what will happen to the solution? 51. For each of the following ionic compounds, write the dissociation equation and state what the value of i would be. a. Sodium Chloride b. Ammonium Carbonate c. Magnesium Nitrate 52. What would be the i value for a soluble covalent, such as ammonia? Why?

7 53. What is the formula for molarity? What unit is used for molarity? 54. What mass of solute would you need to prepare the following solutions? a ml of 1.50 M CCl 4. You must show work to get credit. (Ans g) b. 200 ml of M KBr solution. You must show work to get credit. (Ans g) 55. Colligative properties include boiling point, and freezing point. 56. Would MgCl 2 or NaCl be a more effective salt to put on a highway you are trying to de-ice? Why? 57. Answer the following questions regarding the solubility curve provided: a. What relationship exists between solubility and temperature for the ionic substances shown? b. What relationship exists between solubility and temperature for the gases (SO 2 and NH 3) on the graph? c. A solution of potassium chlorate at 30 C has 20 grams dissolved in 100 grams of water. How would you classify this solution? (Unsaturated, Saturated, or Supersaturated?) d. A solution of sodium nitrate at 30 C has 90 grams dissolved in 100 grams of water. How would you classify this solution? (Unsaturated, Saturated, or Supersaturated?) e. How many grams of sodium nitrate will dissolve in 100 grams of water at 22 C? f. How many grams of sodium nitrate will dissolve in 300 grams of water at 63 C? g. How many grams of ammonium chloride will dissolve in 1000 grams of water at 50 C? h. Ninety grams of sodium nitrate is added to 100 grams of water at 0 C. With constant stirring, to what temperature must the solution be raised to produce a saturated solution with no sodium nitrate solid remaining?

8 58. Fill out the following chart with regards to acids and bases: ACIDS BASES Usually have in the formula: Arrhenius definition says: Bronsted-Lowry s definition says: Has a ph range of: Will turn this color with litmus paper: Will turn this color in phenolphthalein: Will do this when put with a metal: (include identity of gas, if formed) 59. Fill out the following chart with regards to strong vs. weak acids and bases: Strong Acids and Bases Weak Acids and Bases To what % do they ionize? Are they a strong conductor or a poor conductor? Would their ph be closer or farther away from 7 (neutral)? Which arrow do we show in their ionization reaction? 60. What does it mean when we say an acid is polyprotic? 61. What does it mean when we say a substance is amphiprotic? 62. Write the formula for each of the following acids and tell how many hydrogens each of the following acids can give away: a. Sulfuric acid b. Phosphoric acid c. Hydrosulfuric acid d. Acetic acid

9 63. Give the conjugate acid for the following: Give the conjugate base for the following: a. HSO 4 NH 3 b. NH 3 H 2SO 4 c. PO 3 4 HPO 2 4 d. MnO 4 NH Name the following: Write the formula for the following: a. H 2S perchloric acid b. HNO 3 carbonic acid c. H 3PO 3 hydroflouric acid 65. What are the products of a neutralization reaction? 66. On the ph scale, what is acidic, neutral and basic? 67. What is the ph if [OH - ] = 3.7 x 10 5 M? You must show your work for all steps to get credit. a. Is the solution acidic or basic? b. What is the [H + ]? 68. If the ph of a solution is 4.35, what is the hydroxide ion concentration? You must show work for all steps to get credit. a. The hydrogen ion concentration? b. The poh? 69. If the ph of a sodium hydroxide solution is known to be 12.50, what is the hydroxide ion concentration? You must show work for all steps to get credit. (3.16 x 10-2 M) a. The poh? (poh = 1.5) b. The hydrogen ion concentration? (3.16 x M) 70. What is the ph of M barium hydroxide solution? You must show work for all steps to get credit. (ph = 13.49) a. The hydroxide ion concentration? (0.312 M) b. The poh? (poh = 0.51) c. The hydronium ion concentration? (3.20 x M) d. The Barium ion concentration? (0.156 M) 71. What is the molarity of a Sr(OH) 2 solution if 20.0 ml of it is titrated by 25.0 ml of a standard M HCl? You must show work to get credit. (Ans M) 72. If 40.8 ml of M sulfuric acid neutralized 61.8 ml of KOH, what is the concentration of the base? You must show work to get credit. (Ans M)

10 73. Fill in the following portions on the heating curve. 74. What happens to the temperature during a phase change? Why? 75. What is the equation to calculate energy changes when the temperature is raised or lowered? 76. What is the equation to calculate energy changes during a change in state? 77. Use the following picture to answer the next questions a. Which diagram illustrates an endothermic process? b. Which diagram illustrates an exothermic process? c. Which diagram would have a negative value for ΔH? d. Which diagram would have a positive value for ΔH? e. Which diagram would have heat listed as a product? f. Which diagram would have heat listed as a reactant? g. Which container would feel cold when touched? h. Which container would feel warm when touched? 78. The molar heat of fusion, H fus, of Na is 2.6 kj/mol at its melting point, 97.5 o C. How much heat must be absorbed by 5.0 g of solid Na at 97.5 o C to melt it? You must show work to get credit. (Ans kj)

11 79. When 1982 g of water underwent a temperature change from o C to o C, how much energy in kj did the water absorb? The specific heat of water is J/(g o C). You must show work to get credit. (Ans kj) 80. How much energy in kj is required to raise the temperature of g of copper from 22.8 o C to o C? The specific heat of copper is J/(g o C). You must show work to get credit. (Ans kj) 81. Calcium carbide can be made by heating calcium oxide (lime) with carbon (charcoal). CaO (s) + 3 C (s) CaC 2 (s) + CO (g) H = kj How many kilojoules of heat are absorbed in a reaction in which 76.5 g C(s) is consumed? You must show work to get credit. (Ans KJ) 82. How many moles of ethane are required to give off 1.00 x 10 6 kj of heat upon burning? You must show work to get credit. (Ans. 639 mol) 2 C 2H 6 (g) + 7 O 2 (g) 4 CO 2(g) + 6 H 2O(l) H = 3.12 x 103 kj 83. Calculate the standard reaction enthalpy for the following reactions using standard enthalpies of formation. a. 3 NO 2 (g) + H 2O (l) 2 HNO 3 (aq) + NO (g) ( KJ) Substance Ag 2 S (s) H o f (KJ/mol) 32.6 H 2 O (l) H 2 S (g) 20.5 NO 2 (g) b. 2 Ag 2S(s) + 2 H 2O(l) 4 Ag(s) + 2 H 2S(g) + O 2(g) ( KJ) HNO 3 (aq) NO (g) What are the three points of the collision theory? 85. What are the things that will increase the reaction rate of a reaction?

12 86. What is the general format for the rate law formula? 87. What happens to the rate if the reactant is first order and the concentration is doubled? 88. What happens to the rate if the reactant is second order and the concentration is tripled? 89. What happens to the rate if the reactant is zero order and the concentration is doubled? 90. What is the general format for the equilibrium expression? 91. Which states are not included in the equilibrium expression? 92. Match the letters in the diagram with the following descriptions: a. Activation energy of the forward catalyzed reaction. b. Relative energy of the reactants for the forward reaction. c. Relative energy of the products for the forward reaction. d. Difference in energy between the reactants and products. e. Activation energy of the forward uncatalyzed reaction. f. Activation energy of the reverse uncatalyzed reaction. g. Relative energy of the activated complex. 93. Using the diagram, what is the value for ΔH of the forward reaction? 94. Using the diagram, what is the value of ΔH of the reverse reaction?

Gas Laws. Bonding. Solutions M= moles solute Mass %= mass solute x 100. Acids and Bases. Thermochemistry q = mc T

Gas Laws. Bonding. Solutions M= moles solute Mass %= mass solute x 100. Acids and Bases. Thermochemistry q = mc T Name Period Teacher Practice Test: OTHS Academic Chemistry Spring Semester 2017 The exam will have 100 multiple choice questions (1 point each) Formula sheet (see below) and Periodic table will be provided