Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Question 1 Which of the following is a chemical change? Chem 201A Final Exam Review a. Aluminum can crushed by air pressure b. Melting of ice c. Heat from a stove flows through an aluminum pan to the water inside d. The silver spoon used to eat eggs turns black Correct answer is d Question 3 Question 2 How much energy is available if 0.00145 mol of photons are emitted at 295 nm? h = 6.626 x 10-34 Jxs a. 5.88 x 102 J b. 4.05 x 105 J c. 1.02 x 1015 J d. 6.74 x 10-19 J Correct answer is a Which of the following is (are) elements? i) CO ii) Co iii) C iv) Cl2 a. b. c. d. e. v) CaCl2 only iii iii and iv i and v ii, iii and iv ii and iii Correct answer is d Question 4 Question 5 The correct formula of potassium sulfate is The correct formula of ammonium carbonate is a. K2SO3 b. K2S c. KHSO4 d. K(SO4)2 e. K2SO4 a. N2CO3 b. (NH4)2CO3 c. NH4CO3 d. (NH3)2CO3 e. (NH4)4C Correct answer is e Correct answer is b 1 Question 6 Question 7 What’s the empirical formula of a compound consisting of 45.27% carbon, 9.49% hydrogen, and 45.23% oxygen by mass? (Assume 100g of compound). Which is the best pair of solvents for decanoic acid, CH3(CH2)8CO2H a. b. c. d. C5H9O4 C4H9O3 C45H9O45 C4H10O3 Correct answer is a. kerosene b. kerosene c. ethanol d. ethanol e. water d or or or or or aqueous NaOH aqueous HCl water aqueous NaCl aqueous NaOH Correct answer is a Question 8 Question 9 Name the binary compounds PCl5 and S2Cl2. Write the name for Mg(NO3)2 and the formula of cobalt (II) chloride hexahydrate. Are they molecular or ionic? a. Phosphorus pentachloride b. Phosphorus chloride c. Phosphorus (V) chloride d. Phosphorus pentachloride Correct answer is and and and and disulfur dichloride. disulfur dichloride. disulfur dichloride. sulfur (II) chloride. a. Magnesium (II) Nitrite, b. Magnesium (II) Nitrate, c. Magnesium Nitrate, d. Magnesium Nitrate, a Correct answer is CoCl2*6H2O. CoCl2*6H2O. CoCl2*6H2O. CoCl2*6H2O. Ionic. Molecular. Ionic. Molecular. c Question 10 Question 11 The element Rhenium, Re, has two stable isotopes and 18 unstable isotopes. Re-185 has in its nucleus: What mass of CO2 (MM 44.01 g/mol) is formed in the reaction of 233 g of Fe2O3 (MM 159.7 g/mol) with 41.2 g C(s), given the following equation: a. 75 protons, 75 neutrons b. 75 protons, 111 neutrons c. 130 protons, 75 neutrons d. 75 protons, 110 neutrons e. 185 protons, 185 neutrons Correct answer is d a. b. c. d. 3 C(s) 64.2 g 48.1 g 96.3 g 2.19 g + 2 Fe2O3(s) 4 Fe(s) Correct answer is + 3 CO2(g) c 2 Question 12 Question 13 When 1.50 mol of oxygen gas is mixed with 48.7 g of zinc sulfide, the products are solid zinc oxide and sulfur dioxide gas. How many moles of zinc oxide could form in this reaction. Which aqueous solution will have the highest concentration of dissolved particles? a. b. c. d. 0.50 mol 1.5 mol 2.0 mol 1.0 mol Correct answer is a i tetrahedral, trigonal pyramidal, trigonal pyramidal trigonal pyramidal, trigonal pyramidal, trigonal pyramidal tetrahedral, trigonal planar, trigonal pyramidal tetrahedral, trigonal planar, trigonal planar trigonal planar, trigonal planar, trigonal planar a. b. c. d. 6 mol 2 mol 5 mol 3 mol Correct answer is a Question 17 For a complete reaction of Mg (s) + Ge (s) MgGe (s), (balanced) about what mass ratio of the elements should be used? the masses of Mg and Ge will be equal the mass of Mg will be ½ the mass of Ge the mass of Ge will be ½ the mass of Mg the mass of Mg will be three times the mass of Ge the mass of Ge will be three times the mass of Mg Correct answer is If 3 moles of calcium hydroxide are reacted with excess HCl, how many moles of H2O will be produced? c Question 16 a. b. c. d. e. b Question 15 The molecular geometries of central atoms, from left to right, are..? Correct answer is 1.00 mol of NaCl in 1.0 L 1.50 mol of NaCl in 0.5 L 3.00 mol of methanol in 1.0 L 3.00 mol of CaCl2 in 2.0 L Correct answer is Question 14 a. b. c. d. e. a. b. c. d. e How much energy does a refrigerator have to remove from 1.50 kg of water at 20.0 C to cool the water to 2.00 C? Specific heat of water = 4.18 J/g C. a. b. c. d. e. 126 J 113 J 1.13x105 J 1.26x105 J none of the above Correct answer is c 3 Question 18 Question 19 In the lab, a student filled a 500.0 mL container with an unknown gas until a pressure of 380.0 torr was obtained when the temperature was 25 ºC. He then found that the sample of gas weighed 0.164 g. What is the molar mass of the gas? Calculate the H for the synthesis of propane 3 C (s) + 4 H2 (g) C3H8 (g) a. b. c. d. e. 1.34 g/mol 16.0 g/mol 62.3 g/mol 0.0211 g/mol 1.77×10-3 g/mol Correct answer is C3H8(g) + 5O2(g) 3CO2(g) + 4H2O(l) H = -2220 kJ C (s) + O2 (g) CO2 (g) H = -394 kJ H = -286 kJ H2 (g) + ½ O2 (g) H2O (l) a - 106 kJ b b. 106 kJ Correct answer is c. 1540 kJ d. -212 kJ . a Question 20 Question 21 Which pair [or pairs] of solutions will give a precipitate when mixed? What is the pH of a 0.00873 M solution of Ba(OH)2? a. b. c. d. AgNO3(aq) Na2CO3(aq) Fe(NO3)2(aq) NaOH(aq) a. b. c. d. and NaC2H3O2(aq) and Ca(ClO4)2(aq) and NaCl(aq) and CuCl2(aq) Correct answers are b and d Correct answer is How many mL of a 3.59 M solution are needed to make 250.0 mL of a 0.925 M solution? 13.3 mL A 3.00 g sample of copper (II) sulfate pentahydrate (MM of CuSO4 is 159.7 g/mol) is heated until it turns white. What is the mass of the final solid product? a. b. c. d. e. b. 64.4 mL c. c Question 23 Question 22 a. 2.06 1.75 12.25 11.94 970 mL d. 15.5 mL Answer is 1.92 g 2.19 g 2.78 g 2.23 g 1 .87 g Answer is a b 4 Question 24 Using the above MO scheme, what is the bond order of CN–? (show with fingers) Using the above MO scheme, what is the bond order of CN–? B.O. = 3 Question 25 A 25.00 mL sample of sulfuric acid is titrated with 23.59 mL of 0.4159 M NaOH. What is the concentration of the acid? a. b. c. d. • End of review: • 1 more slide for tiebreaker 0.3924 M 0.7848 M 0.004906 M 0.1962 M Answer is d Tie-Breaker Question: Question 25 How much energy must be absorbed to turn 6.00 pounds of ice at -5.0 ºC to water at 20.0 ºC. 1 kg = 2.205 lb Hvap = 40.7 kJ/mol Hfusion = 6.09 kJ/mol Cs ice = 2.09 J/(g ºC) A 25.00 mL sample of sulfuric acid is titrated with 23.59 mL of 0.4159 M NaOH. What is the concentration of the acid? a. b. c. d. e. 1.26x106 kJ 4.35x104 kJ 1.17x103 kJ 7950 kJ 688 kJ Answer is c a. b. c. d. 0.3924 M 0.7848 M 0.1962 M 0.004906 M Answer is c 5 Name these molecular shapes Name these molecular shapes 6