Name ate lass HPTER 9 HPTER SSESSMENT Understanding Main Ideas (Part ) ircle the letter of the choice that best completes the statement or answers the question. 1. In the formation of a covalent bond, electrons are a. shared. b. lost. c. gained. d. transferred. 2. Which of the following elements normally exists in the form of diatomic molecules? a. helium b. argon c. iron d. nitrogen 3. Four electrons are shared in a a. single covalent bond. c. triple covalent bond. b. double covalent bond. d. quadruple covalent bond. 4. Which of the following molecules contains only sigma bonds? a. methane b. oxygen c. carbon dioxide d. nitrogen 5. Which of the following molecules contains a triple bond? a. methane b. oxygen c. carbon dioxide d. nitrogen 6. How many pi bonds are there in a triple bond? a. none b. one c. two d. three 7. Which of the following molecules would be expected to have the greatest bond dissociation energy? a. F 2 b. O 2 c. N 2 d. l 2 In the space at the left, write true if the statement is true; if the statement is false, change the italicized term to make it true. 8. In a chemical name, the prefix used to indicate the presence of two atoms of a given kind is bi-. 9. The prefix hydro- is used in naming binary acids. 10. The oxyacid suffix for an acid that contains an anion ending in -ate is -ic. 11. In Lewis structures, hydrogen is always a terminal atom. 12. In the carbon dioxide molecule, the central atom is a carbon atom. 13. In the compound H 3, the boron atom has more than an octet of electrons. opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 14. The VSEPR model is based on the idea that in a molecule, nuclei repel each other as much as possible. 50 hemistry: Matter and hange hapter 9 hapter ssessment
Name ate lass HPTER 9 STUY GUIE FOR ONTENT MSTERY Section 9.2 Naming Molecules In your textbook, read about how binary compounds and acids are named from their formulas. For each statement below, write true or false. 1. inary molecular compounds are generally composed of a metal and a nonmetal. 2. The second element in the formula of a binary compound is named using the suffix -ite. 3. The prefix tetra- indicates three atoms. 4. The prefix hexa- indicates six atoms. 5. In naming the first element in a formula, the prefix mono- is not used. 6. For binary acids, the hydrogen part of the compound is named using the prefix hydro-. 7. n oxyacid contains only two elements. 8. If the name of the anion of an oxyacid ends in -ate, the acid name contains the suffix -ous. In your textbook, read about naming molecular compounds and oxyacids. For each item in olumn, write the letter of the matching item in olumn. olumn olumn 9. O 10. O 2 11. H 2 O 3 12. NH 3 13. N 2 O 4 14. HNO 2 15. HNO 3 16. Hr 17. HrO 3 a. b. c. d. e. f. g. h. i. hydrobromic acid dinitrogen tetroxide carbon monoxide nitrous acid ammonia nitric acid carbonic acid bromic acid carbon dioxide opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 50 hemistry: Matter and hange hapter 9 Study Guide for ontent Mastery
Name ate lass HPTER 9 STUY GUIE FOR ONTENT MSTERY Section 9.4 Molecular Shape In your textbook, read about the VSEPR model. ircle the letter of the choice that best completes the statement. 1. The VSEPR model is used mainly to a. determine molecular shape. c. determine ionic charge. b. write resonance structures. d. measure intermolecular distances. 2. The bond angle is the angle between a. the sigma and pi bonds in a double bond. c. two terminal atoms and the central atom. b. the nucleus and the bonding electrons. d. the orbitals of a bonding atom. 3. The VSEPR model is based on the idea that a. there is always an octet of electrons around an atom in a molecule. b. electrons are attracted to the nucleus. c. molecules repel one another. d. shared and unshared electron pairs repel each other as much as possible. 4. The shape of a molecule whose central atom has four pairs of bonding electrons is a. tetrahedral. b. trigonal planar. c. trigonal pyramidal. d. linear. 5. The shape of a molecule that has two covalent single bonds and no lone pairs on the central atom is a. tetrahedral. b. trigonal planar. c. trigonal pyramidal. d. linear. 6. The shape of a molecule that has three single covalent bonds and one lone pair on the central atom is a. tetrahedral. b. trigonal planar. c. trigonal pyramidal. d. linear. In your textbook, read about hybridization. Use each of the terms below just once to complete the passage. carbon hybridization sp 3 identical methane The formation of new orbitals from a combination or rearrangement of valence electrons is called (7). The orbitals that are produced in this way are (8) to one another. n example of an element that commonly undergoes such formation is (9). When this atom combines its three opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. p orbitals and its one s orbital, the orbitals that result are called (10) orbitals. n example of a molecule that has this type of orbital is (11). 52 hemistry: Matter and hange hapter 9 Study Guide for ontent Mastery
Name ate lass HPTER 9 STUY GUIE FOR ONTENT MSTERY Section 9.5 Electronegativity and Polarity In your textbook, read about electronegativity. Use the table of electronegativities below to answer the following questions. 1 H 0 3 Li 0.98 11 Na 0.93 19 K 0.82 37 Rb 0.82 55 s 0.79 87 Fr 0.7 4 e 1.57 12 Mg 1.31 20 a 1.00 38 Sr 0.95 56 a 0.89 88 Ra 0.9 21 Sc 1.36 39 Y 1.22 57 La 1.10 89 c 1.1 22 Ti 1.54 40 Zr 1.33 72 Hf 1.3 23 V 1.63 41 Nb 1.6 73 Ta 1.5 Electronegativities of Some Elements 24 r 1.66 42 Mo 2.16 74 W 1.7 25 Mn 1.55 43 Tc 2.10 75 Re 1.9 Metal Metalloid Nonmetal 26 Fe 1.83 44 Ru 76 Os 27 o 1.88 45 Rh 8 77 Ir 28 Ni 1.91 46 Pd 0 78 Pt 29 u 1.90 47 g 1.93 79 u 2.4 30 Zn 1.65 48 d 1.69 80 Hg 1.9 5 2.04 13 l 1.61 31 Ga 1.81 49 In 1.78 81 Tl 1.8 6 2.55 14 Si 1.90 32 Ge 2.01 50 Sn 1.96 82 Pb 1.8 7 N 3.04 15 P 2.19 33 s 2.18 51 Sb 2.05 83 i 1.9 8 O 3.44 16 S 2.58 34 Se 2.55 52 Te 2.1 84 Po 2.0 9 F 3.98 17 l 3.16 35 r 2.96 53 I 2.66 85 t 1. What is the meaning of the term electronegativity? opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 2. Which element has the highest electronegativity? What is the numerical value? What are the name and group number of the chemical family that has the highest overall electronegativities? 3. Which element has the lowest electronegativity? What is the numerical value? What are the name and group number of the chemical family that has the lowest overall electronegativities? 4. What general trend in electronegativity do you note going down a group? cross a period? 5. How are the electronegativity values used to determine the type of bond that exists between two atoms? In your textbook, read about the properties of covalent compounds. For each statement below, write true or false. 6. Ionic compounds are usually soluble in polar substances. 7. In a covalent molecular compound, the attraction between molecules tends to be strong. Study Guide for ontent Mastery hemistry: Matter and hange hapter 9 53
Name ate lass HPTER 9 STUY GUIE FOR ONTENT MSTERY Section 9.5 continued In your textbook, read about bond polarity. Using the table of electronegativities on the preceding page, circle the letter of the choice that best completes the statement or answers the question. 8. Unequal sharing of electrons between two bonded atoms always indicates a. a nonpolar covalent bond. c. a polar covalent bond. b. an ionic bond. d. a polar molecule. 9. When electronegativities of two bonded atoms differ greatly, the bond is a. polar covalent. b. coordinate covalent. c. polar covalent. d. ionic. 10. What is the electronegativity difference that usually is the dividing line between covalent and ionic bonds? a. 1.0 b. 1.7 c. 2.7 d. 4.0 11. The symbol is placed next to which of the following? a. the less electronegative atom in a polar covalent bond c. a positive ion b. the more electronegative atom in a polar covalent bond d. the nucleus 12. nonpolar covalent bond is one in which a. electrons are transferred. c. electrons are shared equally. b. electrons are shared unequally. d. both electrons are provided by the same atom. 13. Molecules containing only polar covalent bonds a. are always polar. c. are always ionic. b. may or may not be polar. d. are always nonpolar. 14. What factor other than electronegativity determines whether a molecule as a whole is polar or not? a. temperature b. its geometry c. its physical state d. its mass 15. Which of the following correctly describes the compound water, H 2 O? a. ionic c. polar overall, with nonpolar covalent bonds b. nonpolar overall, with polar covalent bonds d. polar overall, with polar covalent bonds 16. Which of the following correctly describes the compound carbon tetrachloride, l 4? a. ionic c. polar overall, with nonpolar covalent bonds b. nonpolar overall, with polar covalent bonds d. polar overall, with polar covalent bonds 17. molecule of ammonia, NH 3, is a. nonpolar because it is linear. b. polar because it is linear. c. nonpolar because there is no electronegativity difference. d. polar because there is an electronegativity difference and the molecule is trigonal pyramidal. opyright Glencoe/McGraw-Hill, a division of the McGraw-Hill ompanies, Inc. 54 hemistry: Matter and hange hapter 9 Study Guide for ontent Mastery
HPTER 9 ovalent onding Name: ate: opyright Glencoe/McGraw-Hill, a division of The McGraw-Hill ompanies, Inc. 1 molecule is formed when two or more atoms form a covalent bond. ccording to this definition, which of these is NOT a molecule? Nal H 2 Hl NH 3 This question covers TEKS 2 and 8. This textbook on page 242. Use the table below to answer question 2. 2 The table shows some of the prefixes used to name binary covalent compounds. What name would be given to the compound Pr 5? Number of toms 1 2 3 4 5 Prefix hexaheptaoctanonadeca- monoditritetrapenta- Phosphorus tetrabromide Monophosphorus pentabromide Phosphorus pentabromide Phosphorus hexabromide Number of toms 6 7 8 9 10 Prefix This question covers TEKS 11. This question tests the material that was covered in the textbook on page 248. 3 In the polyatomic ion NH 4 +, the formation of a coordinate covalent bond between nitrogen and hydrogen involves hydrogen transferring a pair of electrons to nitrogen nitrogen transferring a pair of electrons to hydrogen hydrogen donating a pair of electrons to be shared with nitrogen nitrogen donating a pair of electrons to be shared with hydrogen This question covers TEKS 8. This question tests the material that was covered in the textbook on page 257. 4 When hydrogen and fluorine combine, a polar covalent bond is formed. Which of these formulas is the best way to express this relationship? H F + H H F H F F This question covers TEKS 8 and 11. This textbook on page 264. Reviewing hemistry: Mastering the TEKS hemistry: Matter and hange 17
HPTER 9 ovalent onding, continued Name: ate: 5 t room temperature, iodine (I 2 ) is a solid and bromine (r 2 ) is a liquid. These molecules have different melting points because of stronger covalent bonds in iodine covalent bonds in bromine intermolecular forces in iodine intermolecular forces in bromine This question covers TEKS 8. This question tests the material that was covered in the textbook on page 266. 7 Which of these is the chemical formula for sulfurous acid? H 2 S H 2 SO 3 H 2 SO 4 H 2 S This question covers TEKS 11. This question tests the material that was covered in the textbook on page 250. Use the diagram below to answer question 6. 6 The diagram shows the electron configuration of a normal carbon atom and the rearrangement of electrons to form four new identical orbits in a hybridized carbon atom. This type of hybrid orbital is called an 1s 2s 1s 2s s 2 orbital sp orbital sp 2 orbital sp 3 orbital 2p 2p Normal Hybridized This question covers TEKS 8 and 11. This textbook on pages 261 262. 8 The bond that holds two fluorine atoms together in an F 2 molecule would be classified as nonpolar covalent because both atoms are different and the difference in electronegativity is large both atoms are different and the difference in electronegativity is zero both atoms are the same and the difference in electronegativity is large both atoms are the same and the difference in electronegativity is zero This question covers TEKS 2 and 8. This textbook on page 264. opyright Glencoe/McGraw-Hill, a division of The McGraw-Hill ompanies, Inc. 18 hemistry: Matter and hange Reviewing hemistry: Mastering the TEKS