Atoms Molecules Ions 2

Atoms, Molecules, and Ions 2 A periodic table is required to work many of the problems in this chapter. 1. In a cathode ray tube A) electrons pass from the anode to the cathode. B) electrons pass from the cathode to the anode. C) protons pass from the anode to the cathode. D) protons pass from the cathode to the anode. Ans:  B 2. The elements in a column of the periodic table are known as A) metalloids. B) a period. C) noble gases. D) a group. E) nonmetals. Ans:  D 3. Which of the following elements is most likely to be a good conductor of electricity? A) N B) S C) He D) Cl E) Fe Ans:  E 4. An anion is defined as A) a charged atom or group of atoms with a net negative charge. B) a stable atom. C) a group of stable atoms. D) an atom or group of atoms with a net positive charge. Ans:  A 5. The scientist who determined the magnitude of the electric charge of the electron was A) John Dalton. D) Henry Moseley. B) Robert Millikan. E) R. Chang. C) J. J. Thomson. Ans:  B 6. When J. J. Thomson discovered the electron, what physical property of the electron did he measure? A) its charge, e D) its mass, m B) its charge-to-mass ratio, e/m E) its atomic number, Z C) its temperature, T Ans:  B 7. Which of the following scientists developed the nuclear model of the atom? A) John Dalton D) Henry Moseley B) Robert Millikan E) Ernest Rutherford C) J. J. Thomson Ans:  E 8. Rutherford's experiment with alpha particle scattering by gold foil established that A) protons are not evenly distributed throughout an atom. B) electrons have a negative charge. C) electrons have a positive charge. D) atoms are made of protons, neutrons, and electrons. E) protons are 1840 times heavier than electrons. Ans:  A 9. Atoms of the same element with different mass numbers are called A) ions. B) neutrons. C) allotropes. D) chemical families. E) isotopes. Ans:  E 10. How many neutrons are there in an atom of uranium whose mass number is 235? A) 92 B) 143 C) 235 D) 238 E) 327 Ans:  B 11. How many protons are there in an atom of uranium whose mass number is 235? A) 92 B) 143 C) 235 D) 238 E) 327 Ans:  A 12. An atom of the isotope chlorine-37 consists of how many protons, neutrons, and electrons? (p = proton, n = neutron, e = electron) A) 17 p, 18.45 n, 17 e D) 17 p, 37 n, 17 e B) 17 p, 20 n, 7 e E) 20 p, 17 n, 20 e C) 17 p, 20 n, 17 e Ans:  C 13. Give the number of protons (p), electrons (e), and neutrons (n) in one atom of nickel-62. A) 28 p, 28 e, 28 n D) 62 p, 28 e, 28 n B) 28 p, 28 e, 34 n E) 62 p, 62 e, 28 n C) 28 p, 28 e, 62 n Ans:  B 14. Which one of the following is an ion? A) B3+ B) NaCl C) He D) 14C E) none of the above Ans:  A 15. Which one of the following elements is most likely to form a 2+ ion? A) beryllium B) carbon C) fluorine D) oxygen E) sodium Ans:  A 16. Which one of the following elements is most likely to form a 2– ion? A) scandium B) selenium C) silicon D) strontium E) iodine Ans:  B 17. Two isotopes of an element differ in their A) symbol. D) number of protons. B) atomic number. E) number of electrons. C) atomic mass. Ans:  C 18. A magnesium ion, Mg2+, has A) 12 protons and 13 electrons. D) 24 protons and 22 electrons. B) 24 protons and 26 electrons. E) 12 protons and 14 electrons. C) 12 protons and 10 electrons. Ans:  C 19. An aluminum ion, Al3+, has: A) 13 protons and 13 electrons D) 13 protons and 10 electrons B) 27 protons and 24 electrons E) 10 protons and 13 electrons C) 16 protons and 13 electrons Ans:  D 20. An oxide ion, O2–, has: A) 8 protons and 10 electrons D) 8 protons and 7 electrons B) 10 protons and 8 electrons E) 10 protons and 7 electrons C) 8 protons and 9 electrons Ans:  A 21. A phosphide ion has: A) 10 protons and 13 electrons D) 15 protons and 18 electrons B) 12 protons and 15 electrons E) 18 protons and 21 electrons C) 15 protons and 15 electrons Ans:  D 22. An iron(II) ion has: A) 24 electrons and a charge of 2+ D) 28 electrons and a charge of 2+ B) 24 electrons and a charge of 2– E) 28 electrons and a charge of 2– C) 26 electrons and a charge of 2+ Ans:  A 23. How many protons and electrons are present in one Br– ion? A) 35 p, 35 e D) 35 p, 36 e B) 80 p, 81 e E) 80 p, 34 e C) 35 p, 34 e Ans:  D 24. Which of the following pairs of elements would be most likely to form an ionic compound? A) P and Br B) Cu and K C) C and O D) O and Zn E) Al and Rb Ans:  D Section:  2.6 25. Which pair of elements would be most likely to form an ionic compound? A) P and Br B) Zn and K C) F and Al D) C and S E) Al and Rb Ans:  C Section:  2.6 26. Given that the ion ClO3– is named chlorate, what is the ion ClO4– named? A) chloride B) chlorite C) hypochlorite D) perchlorite E) perchlorate Ans:  E 27. What is the formula for the ionic compound formed by calcium ions and nitrate ions? A) Ca3N2 B) Ca(NO3)2 C) Ca2NO3 D) Ca2NO2 E) CaNO3 Ans:  B 28. What is the formula for the ionic compound formed by calcium and selenium? A) CaSe B) Ca2Se C) CaSe2 D) Ca3Se E) CaSe3 Ans:  A Section:  2.6 29. What is the formula for the ionic compound formed by magnesium and iodine? A) MgI B) Mg2I C) MgI2 D) MgI3 E) Mg3I Ans:  C Section:  2.6 30. What is the formula for the binary compound formed by potassium and nitrogen? A) KN B) K2N C) NK2 D) K3N E) NK3 Ans:  D Section:  2.6 31. Predict the formula for the binary compound formed between barium and phosphorus. A) BaP B) Ba2P C) BaP2 D) Ba2P3 E) Ba3P2 Ans:  E Section:  2.6 32. Name the binary compound formed between barium and phosphorus. A) barium phosphorus D) barium diphosphate B) barium phosphide E) barium triphosphide C) barium phosphate Ans:  B 33. Which is the correct formula for copper(II) phosphate? A) Cu2PO4 B) Cu3(PO4)2 C) Cu2PO3 D) Cu(PO4)2 E) Cu(PO3)2 Ans:  B 34. The chemical name for ClO3– is chlorate ion. Therefore, the name of HClO3 is A) hydrochloric acid. D) chlorous acid. B) chloroform. E) chloric acid. C) hydrogen trioxychloride. Ans:  E 35. The chemical name for ClO2– is chlorite ion. Therefore, the name of HClO2 is A) hydrochloric acid. D) chlorous acid. B) chloroform. E) chloric acid. C) hydrogen dioxychloride. Ans:  D 36. Which of the following is the formula for hydrobromic acid? A) KBr B) HBr C) HBrO D) HBrO2 E) HBrO3 Ans:  B 37. The formula for calcium phosphate is A) CaPO4. B) Ca3(PO4)2. C) Ca2(PO4)3. D) Ca3P2. E) Ca3(PO3)2. Ans:  B 38. The formula for magnesium sulfate is A) MnS. B) MgS. C) MnSO3. D) MgSO4. Ans:  D 39. The formula for sodium sulfide is A) NaS. B) K2S. C) NaS2. D) Na2S. E) SeS. Ans:  D 40. The correct name for NH4NO3 is A) ammonium nitrate. D) hydrogen nitrogen oxide. B) ammonium nitrogen trioxide. E) hydrogen nitrate. C) ammonia nitrogen oxide. Ans:  A 41. The correct name for Ba(OH)2 is A) barium hydrogen oxide. D) beryllium hydroxide. B) boron hydroxide. E) barium hydroxide. C) barium hydrate. Ans:  E 42. The correct name for KHCO3 is A) calcium bicarbonate. D) calcium hydrogen carbon trioxide. B) calcium carbonate. E) potassium hydrogen carbonate. C) potassium carbonate. Ans:  E 43. The correct name for CuSO4·5H2O is A) copper sulfate acid. D) copper(II) sulfate pentahydrate. B) copper sulfate pentahydrate. E) copper(V) sulfate hydrate. C) copper(II) sulfate acid. Ans:  D 44. Give the formula for cobalt(II) chlorate dihydrate: A) CoCl2·2H2O D) Co(ClO3)2·2H2O B) CoClO3(H2O)2 E) Co2(ClO3)3·2H2O C) Co(ClO3)2(H2O)2 Ans:  D 45. The Stock system name for Mn2O7 is A) dimanganese heptaoxide. D) manganese(II) oxide. B) magnesium oxide. E) manganese(III) oxide. C) manganese(VII) oxide. Ans:  C 46. The Stock system name for As2S5 is A) arsenic(V) sulfide. D) arsenic(V) sulfate. B) diarsenic pentasulfide. E) diarsenic sulfate. C) arsenic(III) sulfide. Ans:  A 47. Consistent with vanadium being a transition metal, the name for VSO4 should be A) vanadium sulfide. D) vanadium (II) sulfate. B) vanadium (I) sulfite. E) vanadium sulfur tetraoxide. C) vanadium (I) sulfate. Ans:  D 48. Which is the correct formula for lead(IV) chloride? A) Pb4Cl B) PbCl2 C) PbCl3 D) PbCl4 E) Pb2Cl4 Ans:  D 49. The chemical formula for iron(II) nitrate is: A) Fe2(NO3)3 B) Ir(NO2)2 C) Fe2N3 D) Fe(NO3)2 E) Fe(NO2)2 Ans:  D 50. The Stock system name for Co2(SO3)3 is: A) cobalt sulfate D) cobalt(III) sulfite B) cobalt(II) sulfite E) cobalt(III) sulfate C) cobalt(II) sulfate Ans:  D 51. The Stock system name for CrO3 is: A) chromium oxide D) chromium(III) oxide B) chromium(II) oxide E) chromium(VI) oxide C) chromium(III) trioxide Ans:  E 52. The straight chain hydrocarbon that contains six carbon atoms is A) propane. B) butane. C) pentane. D) hexane. E) heptane. Ans:  D Section:  2.8 53. The mineral pyrolusite is a compound of manganese-55 and oxygen-16. If 63% of the mass of pyrolusite is due to manganese, what is the empirical formula of pyrolusite? A) MnO B) Mn2O C) Mn2O2 D) MnO2 E) none of these Ans:  D Category:  Difficult 54. The mineral manganosite is a compound of manganese-55 and oxygen-16. If 77% of the mass of manganosite is due to manganese, what is the empirical formula of manganosite? A) MnO B) Mn2O C) Mn2O2 D) MnO2 E) none of these Ans:  A Section:  2.6 55. The mineral hausmannite is a compound of manganese-55 and oxygen-16. 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 Ans:  C Section:  2.6 56. Zircon is a mineral with the empirical formula ZrSiO4. If all the zirconium is 90Zr, all the silicon is 28Si, and all the oxygen is 16O, what mass of oxygen is present in 10. g of zircon? A) 0.88 g B) 1.2 g C) 1.8 g D) 3.5 g E) 5.4 g Ans:  D 57. The mineral orpiment, having the empirical formula As2S3, was used in ancient times as a cosmetic. What mass of arsenic is present in 5.0 g of orpiment? [Given: naturally occurring arsenic is all arsenic-75; assume that all naturally occurring sulfur is sulfur-32 (only approximately true)] A) 0.61 g B) 3.0 g C) 1.5 g D) 2.0 g E) 3.5 g Ans:  B 58. Which of the following elements is chemically similar to magnesium? A) sulfur B) calcium C) iron D) nickel E) potassium Ans:  B 59. Which of the following elements is chemically similar to oxygen? A) sulfur B) calcium C) iron D) nickel E) sodium Ans:  A 60. Which of the following elements is chemically similar to potassium? A) calcium B) arsenic C) phosphorus D) cerium E) cesium Ans:  E 61. Describe the contributions of Marie Curie. Ans: (note that answers will vary) Marie Curie discovered two new elements, and is one of three people to win two Nobel Prizes. She also suggested the term “radioactivity” to describe the spontaneous emission of particles and/or radiation. 62. What is the law of conservation of mass? Ans: Matter can be neither created nor destroyed. 63. What are the three subatomic particles that are important in chemistry? Ans: electrons, protons, and neutrons 64. What are the three types of radiation produced by the decay of substances like uranium? Ans: Alpha, beta, and gamma radiation 65. How many electrons, protons, and neutrons does an iron-55 atom have? Ans: 26 electrons, 26 protons, and 29 neutrons 66. Define the term molecule. Ans: A molecule is an aggregate of at least two atoms in a definite arrangement held together by chemical forces. 67. What are the seven elements that naturally occur as diatomic molecules? Ans: Hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine 68. Define ion. Ans: An ion is an atom or group of atoms that has a net positive or negative charge. 69. In the early 1900s, Ernest Rutherford performed an experiment with gold foil targets and alpha particles to probe the structure of the atoms. He observed that most of these alpha particles penetrated the foil undeflected. Realizing that atoms are electrically neutral (that is, they have equal numbers of protons and electrons) and that the mass of a proton is significantly greater than the mass of an electron, use Rutherford's data to propose a structural model of an atom. Ans: (Answers will vary.) Atoms are mostly empty space. The mass is concentrated mostly at the center of the atom. Use the following to answer questions 70-76: 70. Use the periodic table above to show where the alkali metals are located. Ans: Group 1A 71. Use the periodic table above to show where the alkaline earth metals are located. Ans: Group 2A 72. Use the periodic table above to show where the metals are located. Ans: Group 2A 73. Use the periodic table above to show where the metalloids are located. Ans: Group 2A 74. Use the periodic table above to show where the nonmetals are located. Ans: Group 2A 75. Use the periodic table above to show where the halogen elements are located. Ans: Group 7A 76. Use the periodic table above to show where the noble gases are located. Ans: Group 8A 77. How many protons are there in one atom of nickel? Ans: 28 78. How many protons are there in one atom of magnesium? Ans: 12 79. How many protons are there in one atom of xenon? Ans: 54 80. How many protons are there in one atom of uranium? Ans: 92 81. A molecule of antifreeze, ethylene glycol, has the formula C2H4(OH)2. How many atoms are there in one molecule of antifreeze? Ans: 10 82. What is the total number of atomic particles (protons, neutrons, and electrons) in an atom of 3H? Ans: 4 83. What is the total number of atomic particles (protons, neutrons, and electrons) in an atom of 40Ca? Ans: 60 84. What is the total number of atomic particles (protons, neutrons, and electrons) in an atom of 18F? Ans: 27 85. How many atoms are in one molecule of CaCl2? Ans: 3 86. How many atoms are in one molecule of C6H12O6? Ans: 24 87. Give the formula for potassium oxide. Ans: K2O 88. Give the formula for calcium chloride. Ans: CaCl2 89. Give the formula for carbon disulfide. Ans: CS2 90. Give the formula for lithium hydroxide. Ans: LiOH 91. Give the formula for nickel(II) sulfate. Ans: NiSO4 92. Name the following binary compound: FeS. Ans: iron(II) sulfide 93. Name the following binary compound: NaH. Ans: sodium hydride 94. Name the following binary compound: MnCl2. Ans: manganese(II) chloride 95. Name the following binary compound: AgCl. Ans: silver chloride; may accept silver(I) chloride. 96. Name the following binary compound: Fe2O3. Ans: iron(III) oxide (or ferric oxide) 97. Name the following ternary compound: CuCO3. Ans: copper(II) carbonate 98. Name the following ternary compound: FeSO4. Ans: iron(II) sulfate 99. Name the following ternary compound: Na3PO4. Ans: sodium phosphate 100. Name the following ternary compound: Al(NO3)3. Ans: aluminum nitrate 101. Name the following compound: Cl2O7. Ans: dichlorine heptaoxide, or dichlorine heptoxide 102. Name the straight chain hydrocarbon that contains eight carbon atoms. Ans: octane Section:  2.8 103. The table below describes four atoms. Atom A Atom B Atom C Atom D Number of protons 79 80 80 79 Number of neutrons 118 120 118 120 Number of electrons 79 80 80 79 Which atoms represent the same element? Ans: Atoms A and D represent the same element, and atoms B and C represent the same element. 104. Consider a neutral atom of the following isotope of sulfur: How many electrons, protons, and neutrons does the atom contain? Ans: 16 electrons, 16 protons, and 18 neutrons 105. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of calcium? Ans: 20 electrons, 20 protons, and 24 neutrons 106. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of krypton? Ans: 36 electrons, 36 protons, and 48 neutrons 107. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of gadolinium? Ans: 64 electrons, 64 protons, and 96 neutrons 108. Write the names and symbols of two metals and two nonmetals. Identify which are the metals and which are the nonmetals. Ans: (Answers will vary.) Metals: iron, Fe; sodium, Na; etc. Nonmetals: chlorine, Cl; nitrogen, N; etc. 109. Predict the formula for the binary compound formed between potassium and sulfur. Ans: K2S Section:  2.6 110. Predict the formula for the binary compound formed between aluminum and fluorine. Ans: AlF3 Section:  2.6 111. Give the formula of magnesium nitrate. Ans: Mg(NO3)2 112. Give the formula of calcium phosphate. Ans: Ca3(PO4)2 113. Give the formula of iron(II) phosphate. Ans: Fe3(PO4)2 114. Give the formula of copper(II) bromide. Ans: CuBr2 115. Give the formula of ammonium sulfate. Ans: (NH4)2SO4 116. Give the formula of hydrochloric acid. Ans: HCl 117. Give the formula of carbonic acid. Ans: H2CO3 118. Give the formula of nitric acid. Ans: HNO3 119. Give the formula of sulfuric acid. Ans: H2SO4 120. Write the formula for the acid formed from the fluoride anion, and then name the acid. Ans: HF, hydrofluoric acid 121. Write the formula for the acid formed from the nitrite anion, and then name the acid. Ans: HNO2, nitrous acid 122. Write the formula for the acid formed from the permanganate anion, and then name the acid. Ans: HMnO4, permanganic acid 123. Write the formula for the acid formed from the hydrogen sulfate anion, and then name the acid. Ans: H2SO4, sulfuric acid 124. The elements known as the halogens are useful as disinfectants. Name two halogens. Ans: (two of these) fluorine, chlorine, bromine, iodine 125. Define allotrope. Ans: An allotrope is one of the two or more distinct forms of an element. Section:  2.6 126. What are isotopes? Ans: Atoms of the same element that have the same atomic number but different mass numbers. 127. Name the following compound: NaNO2. Ans: sodium nitrite 128. Name the following compound: KCl. Ans: potassium chloride 129. Name the following compound: Mg(NO3)2. Ans: magnesium nitrate 130. Write the formula of ammonium chlorate. Ans: NH4ClO3 131. Write the formula of lead(II) chloride. Ans: PbCl2 132. Write the formula of calcium carbonate. Ans: CaCO3 133. The formula for isopropyl alcohol is sometimes written as (CH3)2CHOH to better indicate how the atoms are connected. How many hydrogen atoms would be contained in 3 dozen isopropyl alcohol molecules? Ans: 288 134. Almost all the mass of an atom is concentrated in the nucleus. Ans:  True Category:  Easy 135. Marie Curie suggested the name “radioactivity” to describe the spontaneous emission of particles and/or radiation. Ans:  True Category:  Easy 136. Using a cathode ray tube, J. J. Thomson determined the magnitude of the electric charge on the electron. Ans:  False Category:  Easy 137. When a beam of alpha particles passes between two electrically charged plates, the beam is deflected toward the positive plate. Ans:  False Category:  Medium 138. The proton is about 1840 times heavier than the electron. Ans:  True Category:  Easy 139. The atomic number is equal to the number of protons in the nucleus of each atom of an element. Ans:  True Category:  Easy 140. The number of neutrons in all atoms of an element is the same. Ans:  False Category:  Medium 141. An empirical formula tell us which elements are present in a compound and gives us the simplest, whole-number ratio of the atoms of these elements in the compound. Ans:  True Category:  Medium