CHEM 1151 Review Chapter 3 and 4 Chapter 3: Molecules, Compounds, and Chemical Formulas

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1 CHEM 1151 Review Chapter 3 and 4 Chapter 3: Molecules, Compounds, and Chemical Formulas 1. What are the two different ions present in the compound FeCl3? A) Fe 2+, Cl 3- B) Fe 3+, Cl 3- C) Fe +, Cl - D) Fe 3+, Cl - E) Fe +, Cl - 2. What are the ions present in the compound CH4? A) C 4+, H + B) C 4-, H + C) C -, H + D) C 4- H 4+ E) no ions present 3. Which of the following is an example of an empirical formula? A) C9H12 B) C9H18Cl2 C) C6H6 D) N2O4 E) C2H2O2 4. Which is the correct formula for iron(ii) phosphate? A) Fe2PO4 B) Fe3(PO4)2 C) Fe2PO3 D) Fe(PO4)2 E) Fe(PO3)2 5. Which of the following is the formula for hydroiodic acid? A) HIO4 B) HIO3 C) HIO2 D) HIO E) HI 6. The name for Ba(OH)2 is A) barium hydrogen oxide. D) beryllium hydroxide. B) boron hydroxide. E) barium hydroxide. C) barium hydrate. 7. The name for KHCO3 is A) calcium bicarbonate. D) calcium hydrogen carbon trioxide. B) calcium carbonate. E) potassium hydrogen carbonate. C) potassium carbonate. 8. Name the compound Co(NO3)2 A) Cobalt (I) nitrate D) Cobalt nitrite B) Cobalt (II) nitrate E) Cobalt (II) nitride C) Cobalt (I) nitride

2 9. Name the acid H2SO3 (dissolved in water). A) Sulfuric acid D) Persulfuric acid B) Sulfurous acid E) Hyposulfurous acid C) Hydrosulfuric acid 10. Name the compound CrO3. A) chromium oxide D) chromium(iii) oxide B) chromium(ii) oxide E) chromium(vi) oxide C) chromium(iii) trioxide 11. Name the compound Cl2O5 A) chlorine pentoxide D) chloride oxide B) dichlorine pentoxygen E) dichloride pentoxide C) dichlorine pentoxide 12. Name the compounds SO3 A) sulfur trioxide B) sulfate C) sulfite D) sulfur trioxygen E) sulfur oxide 13. How many O atoms are in 4.39 g of CO2? A) 5.29 x O atoms D) 6.01 x O atoms B) 1.03 x O atoms E) 1.20 x O atoms C) 1.65 x O atoms 14. Formaldehyde has the formula CH2O. How many molecules are there in 0.11 g of formaldehyde? A) B) C) 4.0 D) E) How many sulfur atoms are there in 21.0 g of Al2S3? A) atoms D) atoms B) atoms E) atoms C) atoms 16. Calculate the mass of O in 4.36 g of Cl2O7? A) 30.5 g O B) 48.8 g O C) 11.2 g O D) 69.8 g O E) 2.67 g O 17. How many grams of nitrogen are there in 7.5 g of Ca(NO3)2? A) 0.64 g B) 1.3 g C) 0.15 g D) 1.2 g E) 2.3 g

3 18. What is the mass of UF6 molecules? A) 352 g B) g C) g D) g E) g 19. The mineral hausmannite is a compound of 55 Mn and 16 O. If 72% of the mass of hausmannite is due to manganese, what is the empirical formula of hausmannite? A) MnO B) Mn3O C) Mn3O4 D) Mn4O3 E) MnO3 20. An unknown compound with a molar mass of g/mol consists of 32.18% C, 4.50% H, and 63.32% Cl. Find the molecular formula for the compound. A) CHCl B) C6H10Cl4 C) C3H5Cl2 D) C9H15Cl6 E) C6H10Cl2 21. What is the coefficient of H2O when the following equation is properly balanced? Al4C3 + H2O Al(OH)3 + CH4 A) 3 B) 4 C) 6 D) 12 E) What is the coefficient for O2 when the following combustion reaction of a fatty acid is properly balanced? C18H36O2 + O2 CO2 + H2O A) 1 B) 8 C) 9 D) 26 E) Balance the following and list the coefficients in order from left to right. Cr + H2SO4 Cr2(SO4)3 + H2 A) 2, 3, 1, 2 B) 2, 3, 1, 3 C) 1, 3, 1, 3 D) 4, 6, 2, 6 E) 1, 3, 1, Ammonia reacts with hydrochloric acid to produce ammonium chloride. Identify the balanced reaction that describes this process. A) NH4 + + HCl NH4Cl + H D) NH HCl NH4Cl2 B) NH3 + HCl NH4Cl E) NH3 + 2HCl NH4Cl2 C) NH3 + 2HCl NH4Cl + H 25. Aluminum metal reacts with nitric acid to produce aluminum nitrate and hydrogen gas. Identify the balanced reaction that describes this process. A) Al + HNO3 AlNO3 + H2 D) Al + 3HNO3 Al(NO3)3 + H2 B) Al + HNO3 AlNO3 + H E) 2Al + 6HNO3 2Al(NO3)3 + 3H2 C) Al + 2HNO3 Al(NO3)2 + H2 26. A g sample of mannitol, a sugar found in seaweed, is burned completely in oxygen to give g of carbon dioxide and g of water. The empirical formula of mannitol is A) CHO B) CH7O3 C) C3H2O D) C3H7O3 E) CH2O

4 27. A g sample of sorbic acid, a compound first obtained from the berries of a certain ash tree, is burned completely in oxygen to give g of carbon dioxide and g of water. The empirical formula of sorbic acid is A) CH2O B) C3H4O C) CH4O3 D) C3H4O2 E) C2H4O2 28. The Mass % of F in KrF2 is. A) B) C) D) E) Calculate the percentage by mass of hydrogen in PtCl2(NH3)2 A) B) C) D) E) g of copper metal is converted into 6.45g CuO. In another experiment 1.10g copper produced 1.37g CuO on combustion. Calculate the percent by mass of oxygen for both experiments to show that the data verifies the law of definite proportion. Ans: % O = 19.7% and % O = 19.7% Oxygen percentages are the same for both experiments which supports definite proportions. Chapter 4: Chemical Quantities and Aqueous Reactions 1. Phosphorus pentachloride reacts with water to form hydrochloric acid and phosphoric acid. How many total moles of acid are formed when starting with 4.5 g of PCl5 and excess H2O? PCl5 + 4H2O 5HCl + H3PO4 A) moles B) 0.12 moles C) 0.13 moles D) 27 moles E) 23 moles 2. What is the theoretical yield of chromium that can be produced by the reaction of 40.0g of Cr2O3 with 8.00 g of aluminum according to the chemical equation below? 2Al + Cr2O3 Al2O3 + 2Cr A) 7.7 g B) 15.4 g C) 27.3 g D) 30.8 g E) 49.9 g 3. What is the theoretical yield of vanadium that can be produced by the reaction of 40.0g of V2O5 with 40.0 g of calcium based on the following chemical reaction? V2O5(s) + 5Ca(l) 2V(l) + 5CaO(s) A) 5.6 g B) 11.2 g C) 20.3 g D) 22.4 g E) 40.0 g

5 4. The reaction of 60.0 g of aluminum oxide with 30.0 g of carbon produced 22.5 g of aluminum. What is the percent yield for this reaction? Al2O3 + 3C 2Al + 3CO A) 25.0 % B) 31.8 % C) 44.9 % D) 50.1 % E) 70.9 % 5. The first step in the Ostwald process for producing nitric acid is 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g). If the reaction of 150. g of ammonia with 150. g of oxygen gas yields 87. g of nitric oxide (NO), what is the percent yield of this reaction? A) 33% B) 49% C) 62% D) 77% E) 100% 6. Aluminum hydroxide reacts with nitric acid to form aluminum nitrate and water. What mass of water can be formed by the reaction of 15.0 g of aluminum hydroxide with excess nitric acid? A) 1.15 g B) 3.46 g C) 6.14 g D) 10.4 g E) 45.0 g 7. Which of the following will occur when a solution of Pb(NO3)2(aq) is mixed with a solution of KI(aq)? A) A precipitate of KNO3 will form; Pb 2+ and I are spectator ions. B) No precipitate will form. C) A precipitate of Pb(NO3)2 will form; K + and I are spectator ions. D) A precipitate of PbI2 will form; K + and NO3 are spectator ions. E) A precipitate of PbI2 will form; Pb 2+ and I are spectator ions. 8. Which of the following will occur when solutions of ZnSO4(aq) and MgCl2(aq) are mixed? A) A precipitate of ZnCl2 will form; Mg 2+ and SO4 2 will be spectator ions. B) A precipitate of ZnSO4 will form ; Mg 2+ and Cl will be spectator ions. C) A precipitate of MgSO4 will form ; Zn 2+ and Cl will be spectator ions. D) A precipitate of MgCl2 will form ; Zn2 + and SO4 2 will be spectator ions. E) No precipitate will form. 9. Identify the correct net ionic equation for the reaction that occurs when solutions of Pb(NO3)2 and NH4Cl are mixed. A) Pb(NO3)2(aq) + 2NH4Cl(aq) NH4NO3(aq) + PbCl2(s) B) Pb 2+ (aq) + 2Cl (aq) PbCl2(s) C) Pb 2+ (aq) + 2NO3 (aq) + 2NH4 (aq) + 2Cl (aq) 2NH4 (aq) + 2NO3 (aq) +PbCl2(s) D) NH4 + (aq)+ NO3 (aq) 2NH4NO3(s) E) No reaction occurs when the solutions are mixed.

6 10. Identify the correct net ionic equation for the reaction that occurs when solutions of Na3PO4 and Ca(NO3)2 are mixed A) Ca 2+ + PO4 2- (aq) CaPO4(s) B) 3Ca 2+ (aq) + 2PO4 3- (aq) Ca3(PO4)2(s) C) Na + (aq) + NO3 - NaNO3(s) D) Na + (aq) + Ca 2+ (aq) + PO4 3- (aq) NaCaPO4(s) E) 2 Na3PO4(aq) + 3Ca(NO3)2(aq) 6NaNO3(s) + Ca3(PO4)2(s) 11. Which of the following compounds is a strong acid? A) HF B) HI C) HClO2 D) H2SO3 E) HNO2 12. Which of the following ions is a weak acid? A) SO4 2- B) H2SO4 C) H2SO3 D) HNO3 E) NO3-13. The oxidation number of S in K2SO4 is A) +6 B) +4 C) +2 D) 1 E) None of the above. 14. The oxidation number of Mn in KMnO4 is A) +8 B) +7 C) +5 D) 7 E) The oxidation number of Fe in K3Fe(CN)6 is A) +3 B) +2 C) +1 D) 3 E) The oxidation number of Cr in Cr2O7 2 is A) 12 B) 7 C) 2 D) +6 E) Using the redox reaction below determine which element is oxidized and which is reduced. 4NH3 + 3Ca(ClO)2 2N2 + 6H2O + 3CaCl2 A) H is oxidized and N is reduced D) Cl is oxidized and O is reduced B) N is oxidized and Cl is reduced E) Cl is oxidized and N is reduced C) N is oxidized and O is reduced 18. How many total electrons are transferred in the following reaction? B2H6(g) + 3O2(g) 2 3(s) + 3H2O(l) A) 2 B) 3 C) 4 D) 6 E) 12

7 19. Which one of the following is a redox reaction? A) 2Al(s) + 3H2SO4(aq) Al2(SO4)3(aq) + 3H2(g) B) 2KBr(aq) + Pb(NO3)2(aq) 2KNO3(aq) + PbBr2(s) C) CaBr2(aq) + H2SO4(aq) CaSO4(s) + 2HBr(g) D) H+(aq) + OH (aq) H2O(l) E) CO3 2 (aq) + HSO4 - (aq) HCO3 (aq) + SO4 2 (aq) 20. Which of the following equations does not represent an oxidation-reduction reaction? A) 3Al + 6HCl 3H2 + AlCl3 B) 2H2O 2H2 + O2 C) 2NaCl + Pb(NO3)2 PbCl2 + 3NaNO3 D) 2NaI + Br2 2NaBr + I2 E) Cu(NO3)2 + Zn Zn(NO3)2 + Cu 21. In the following chemical reaction the oxidizing agent is 5H2O2 + 2MnO4 + 6H + 2Mn H2O + 5O2 A) H2O2 B) MnO4 C) H + D) Mn 2+ E) O2 22. Identify the reducing agent in the following chemical reaction. 5Fe 2+ (aq) + MnO4 (aq) + 8H + (aq) 5Fe 3+ (aq) + Mn 2+ (aq) + 4H2O(l) A) Fe 2+ B) MnO4 C) H + D) Mn 2+ E) Fe Which of the following is NOT a redox reaction? A) 2NaN3(s) 2Na(s) + 3N2(g) B) Fe2O3(s) + 2Al(s) 2Fe(s) + Al2O3(s) C) 3NO2(g) + H2O(l) 2HNO3(aq) + NO(g) D) NH4Cl(aq) + AgNO3 NH4NO3(aq) + AgCl(s) E) 2ZnS(s) + 3O2(g) 2ZnO(s) + 2SO2(g) 24. Which of the following represents an acid-base neutralization reaction? A) 2Al(s) + 3H2SO4(aq) Al2(SO4)3(aq) + 3H2(g) B) SO2(g) + H2O(l) H2SO3(g) C) LiOH(aq) + HNO3(aq) LiNO3(aq) + H2O(l) D) 2KBr(aq) + Cl2(g) 2KCl(aq) + Br2(l) E) CaBr2(aq) + H2SO4(aq) CaSO4(s) + 2HBr(g)

8 25. Which of the following represents a combustion reaction? A) 2C2H6(g) + 7O2(g) 4CO2(g) + 6H2O(l) B) LiOH(aq) + HNO3(aq) LiNO3(aq) + H2O(l) C) N2(g) + 3H2(g) 2NH3(g) D) 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g) E) 2Al(s) + 3H2SO4(aq) Al2(SO4)3(aq) + 3H2(g) 26. What type of reaction is the following? Ca(OH)2(s) + 2 HNO3(aq) Ca(NO3)2(aq) + 2 H2O(l) A) Combination reaction D) gas evolution reaction B) Acid-base neutralization reaction E) Combustion reaction C) Oxidation/reduction reaction 27. What mass of C6H12O6 (glucose) is needed to prepare 450. ml of a M solution of glucose in water? A) g B) 293 g C) g D) 52.7 g E) 125 g 28. A 50.0 ml sample of M NH4NO3 is diluted with water to a total volume of ml. What is the ammonium nitrate concentration in the resulting solution? A) 21.8 M B) M C) M D) M E) M 29. A ml sample of M nitric acid is introduced into a flask, and water is added until the volume of the solution reaches 250. ml. What is the concentration of nitric acid in the final solution? A) 1.27 M D) M B) M E) M C) M ml of M NaOH was needed to neutralize 50.0 ml of an H2SO4 solution. What is the concentration of the original sulfuric acid solution? A) M B) M C) M D) M E) M 31. What volume (ml) of a M HCl(aq) solution is required to completely neutralize ml of a M Ba(OH)2(aq) solution? A) ml B) ml C) ml D) ml E) ml

9 32. Which combination will produce a precipitate? A) NH4OH (aq) and HCl (aq) B) AgNO3 (aq) and Ca(C2H3O2)2 (aq) C) NaOH (aq) and HCl (aq) D) NaCl (aq) and HC2H3O2 (aq) E) NaOH (aq) and Fe(NO3)2 (aq)