Chemistry 11 Unit 2: Chemical Bonding Test Prep. 1. The transfer of two electrons from one atom to another will result in a bond that is a.

Transcription

1 Chemistry 11 Unit 2: Chemical Bonding Test Prep Chemist: Part 1: Identify the letter of the choice that best completes the statement or answers the question. 1. The transfer of two electrons from one atom to another will result in a bond that is divalent ionic covalent Polar isoelectonic 2. The electron configurations of elements H, J, L, M, and R are as follows: H: 2, 8, 5 J: 2, 3 L: 2, 8, 8, 2 M: 2, 8, 6 R: 2, 7 The element most likely to form an ion having a charge of 2 is M L J H R 3. For a bond to be polar, it is necessary that more than one pair of electrons be shared there is an unsymmetrical distribution of electric charge one of the atoms be highly electronegative one atom be from a metal and the other from a non-metal only atoms of non-metals are involved in the bond 4. Which molecule violates the octet rule? 5. Which element will form a covalent bond with nitrogen? 1

2 Na Be Fe Sr N 6. Which Lewis structure is incorrect? 7. Refer to a table of electronegativities and determine which bond is most polar. I Cl Be S C H S Cl O P 8. What is the correct Lewis structure for any element X in Group 16 (VIA) of the periodic table? 9. When the element strontium combines with a halogen to form a compound, the charge on each halogen ion is The total number of electrons found in a molecule represented by the structural formula shown below is In which compound is the covalent bonding an exception to the octet rule? 2

3 CCl CO PCl NF H O 12. Examine the structural formula below. Which bond is most polar? N H C C C O C N O H 13. Refer to a table of electronegativities and determine in which compound(s) the bonding would be classified as ioni I. K O II. CO III. FeCl IV. Mg P V. CoCl I III, IV, and V I, III, IV, and V II I and V 14. Refer to a table of electronegativities and determine in which compound(s) the bonding would be classed as polar covalent. I. Na O II. SO III. IrCl IV. MgF V. CH I and IV II and V III and IV V II and III 3

4 15. Refer to a table of electronegativities and determine in which compound(s) the bonding would be classifed as covalent. I. CO II. F O III. MgF IV. BrCl V. CF I and V IV V III I, II, and V 16. Which physical property is identified with a molecular compound? low melting point high solubility in water electrical conductivity in the liquid state rarely found as a gas usually found as a crystalline solid 17. The most significant factor that determines the type of bond that forms between two atoms is the element s nuclear charge electronegativity number of energy levels melting point number of inner electrons 18. If the letter Z is used to represent any member of Group 14 (IVA) in the periodic table, what is the general formula for the fluorine compounds of Z? ZF ZF ZF ZF ZF 19. Which representation of a stable ion of calcium is correct? Ca: [Ca] [Ca] Ca [Ca] 20. Which compound has negative and positive ions with identical electron configurations? CaF KF MgCl LiF KCl 21. Which chemical species have the same total number of valence electrons as a molecule of carbon monoxide, CO? I. O II. NO IV. CN III. NO 4

5 I and III II and III I and IV II and IV II, III, and IV 22. Which Lewis structures correctly predict the formula for the compound formed between cesium and oxygen? 23. The diagram below is used to indicate a large difference in the electronegativities of O and F that O is more electronegative than F that the electrons in the bond between O and F are shared equally that the oxygen end of the bond is more negative than the fluorine end the direction of the bond dipole between O and F 24. Which structural formula shown below is not possible according to the octet rule? I. II. 5

6 III. IV. V. I II III IV V 25. The correct structural formula for HCN is I. II. III. IV. V. I II III IV V _ 6

7 26. The correct structural formula for OCl 2 is: I. II. III. IV. V. I II III IV V 27. What is the correct chemical formula for the molecule shown below? C H O C H C H O C H O C H O 29. Select the statement that is correct. A C=C bond is shorter than a C C bon Carbon can form polar covalent bonds with other carbon atoms. A fluorine atom can accept more than one electron to form an ionic bon A covalent bond forms when the forces of attraction and the forces of repulsion between two atoms are at a maximum. All ionic bonds have 100% ionic character. 30. Predict the order in which the bond dipoles will increase in a hypothetical molecule having a hydrogen atom and three different halogen atoms bonded to a single carbon atom, CHFClBr. C F, C Cl, C Br, C H C H, C F, C Cl, C Br C F, C Cl, C H, C Br C H, C Br, C Cl, C F C Br, C H, C Cl, C F 7

8 31. Select the structural formulas that could represent a molecule of C H O and be in agreement with the octet rul I. II. III. IV. V. I, III, and V III II I and III II, III, and IV 32. Which Lewis structures correctly show the bonding between the elements antimony and hydrogen? 8

9 33. What is the most likely charge on the stable ion of an element in Group 16 (VIA) of the periodic table? Atoms of the metal element X have one valence electron and atoms of the non-metal element Y have six valence electrons. Which Lewis structure correctly represents the way in which these elements combine? 35. Which compound is least likely to conduct an electric current when dissolved in water? NaNO CaCl C H MgBr CsF 36. Refer to a table of electronegativities and determine which pair of elements will form a compound having the most ionic character. Co and Br Mg and O Fe and C Si and F K and Cl 9

10 37. Which Lewis strucure is correct? [Mg] [Be] 38. The electrostatic attractive force between the free electrons and positive metal ions is a/an ionic bond metallic bond polar covalent bond Dipole covalent bond 39. Across period 3 of the periodic table, the compounds NaCl, MgCl, AlCl, SiCl, PCl, S Cl, and Cl will demonstrate a decrease in metallic bonding an increase in EN an increase in polarity of the bonds an increase in melting point a bonding continuum 40. Which group of the periodic table contains elements that form compounds mainly through covalent bonding? 17, (VIIA) 2, (IIA) 13, (IIIA) 1, (IA) 14, (IVA) 41. When an atom of hydrogen forms a covalent bond with another atom, the number of electrons in the valence shell of the hydrogen atom is the same as the electron configuration in an atom of Li He Ne F O 42. Which Lewis structure represents a molecule with a stable electron configuration? 10

11 43. Which of the following is correct? 44. From the list of stable ions shown below, which are most likely metal ions? I. X II. X III. X IV. X 11

12 V. X I, IV, and V III and IV II, IV, and V IV and V I and IV 45. The units of pure substances that have pure covalent bonds are called metal crystal lattices ion pairs covalent crystals molecules ionic solids 46. Which substance is expected to have bonding with the highest percent ionic character? H O Cl CsF MgO PH 47. Which structural formula for the molecule COCl shows the correct directions for the bond dipoles? 12

13 48. Which of the following conducts an electric current? I. Na(s) II. NaCl( ) III. NaCl(s) I and V I, II, and V IV IV. Cl (s) V. NaCl(aq) V II and V 49. Which compound listed below is best described as an ionic compound? I. KNO II. SO III. Br I II III IV. C H V. SiH IV V 50. Which pair of substances both correctly match the following properties: good conductors of electricity and high melting point? NaF(aq) and Br ( ) Pb(s) and Mg(s) S(s) and H O( ) NaCl(s) and Hg( ) Cu(s) and P (s) 51. Which pair of substances would both be considered good conductors of electricity? Cu(s) and CuCl (s) CH ( ) and Pb(s) Mg(s) and MgCl (aq) NH ( ) and NaCl( ) NaCl( ) and CO (s) 52. A homonuclear diatomic molecule has two identical ions bonded together three identical atoms in a molecule only single bonds electronegativities that cancel two identical atoms covalently bonded 53. The substance that would be expected to have a very low melting point is H O(s) O (s) Pb(s) C(s) CuCl (s) 54. A compound is made up of different atoms covalently bonded together. Based only on this information, it can be said with certainty that in the solid state, this compound likely will conduct an electric current this compound does not dissolve in water in the liquid state, this compound will conduct an electric current this compound will have a high melting point 13

14 this compound is made up of molecules 55. The maximum number of electrons that an atom can contribute to a bond with one other atom is six eight two One three 56. The molecule shown below has: three types of bonds one homonuclear diatomic bond polar covalent bonds only three polar covalent bonds and one pure covalent bond six polar covalent bonds and one pure covalent bond 57. A compound is soluble in water and its aqueous solution is a good conductor of electricity. This compound is likely malleable made up of ions a conductor of electricity in the solid state to have covalent bonds between its atoms a gas at room temperature 58. A trend that is observed going down Group 14 (IVA) of the periodic table, is the electronegativity of the elements increase the elements have a greater tendency to share electrons in covalent bonds the elements become less malleable there is a greater tendency for the elements to form ions the size of the atoms decrease 59. Which molecule has no lone pairs of electrons? H NH H O CCl HF 60. Which molecule must have a multiple bond (double or triple) for the octet rule to hold? C H CHCl CF CH Cl C H 61. How would you describe the bond in a molecule of HCl? polar covalent triple bond non-polar covalent hydrogen bond double bond 14