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Exercises
Chemical Bonding: Basic Ideas
*01. What type of force is responsible for chemical bonding? Explain the differences between ionic bonding and covalent bonding. *02. What kind of bonding (ionic or covalent) would you predict for the products resulting from the following combinations of elements? (a) Na Cl2; (c) N2 O2, (b) C O2; (d) S O2. *03. Why are covalent bonds called directionalbonds, whereas ionic bonding is termed nondirectional? *04. (a) What do Lewis dot formulas for atoms show? (b) Write Lewis dot formulas for the following atoms: He; Si; P; Ne; Mg; Br. *05. Write Lewis dot formulas for the following atoms: Li; B; As; K; Xe; Al. *06. Describe the types of bonding in sodium chlorate, NaClO3.
O Na O Cl O

*07. Describe the types of bonding in ammonium chloride,NH4Cl.
H H N H H Cl

*08. Based on the positions in the periodic table of the following pairs of elements, predict whether bonding between the two would be primarily ionic or covalent. Justify your answers. (a) Ca and Cl; (b) P and O; (c) Br and I; (d) Li and I; (e) Si and Br; (f ) Ba and F. *09. Predict whether the bonding between the following pairs of elements would be primarily ionic orcovalent. Justify your answers. (a) Rb and Cl; (b) N and O; (c) Ca and F; (d) P and S; (e) C and F; (f ) K and O. *10. Classify the following compounds as ionic or covalent: (a) Ca(NO3)2; (b) H2S; (c) KNO3; (d) CaCl2; (e) H2CO3; (f ) PCl3; (g) Li2O; (h) N2H4; (i) SOCl2.

Ionic Bonding
*11. Describe what happens to the valence electron(s) as a metal atom and a nonmetal atom combine to form an ioniccompound. *12. Describe an ionic crystal. What factors might determine the geometrical arrangement of the ions? *13. Why are solid ionic compounds rather poor conductors of electricity? Why does conductivity increase when an ionic compound is melted or dissolved in water? *14. Write the formula for the ionic compound that forms between each of the following pairs of elements: (a) Ca and Br2; (b) Baand Cl2; (c) Na and Cl2. *15. Write the formula for the ionic compound that forms between each of the following pairs of elements: (a) Cs and F2; (b) Sr and S; (c) Na and Se. *16. When a d-transition metal ionizes, it loses its outer s electrons before it loses any d electrons. Using [nobel gas] (n 1) d x representations, write the outer-electron configurations for the following ions: (a) Cr3 ; (b)Mn2 ; (c) Ag ; (d) Fe3 ; (e) Cu2 ; (f ) Sc3 ; (g) Fe2 . *17. Which of the following do not accurately represent stable binary ionic compounds? Why? BaCl2; NaS; AlF4; SrS2; Ca2O3; NaBr2; LiSe2. *18. Which of the following do not accurately represent stable binary ionic compounds? Why? MgI; Al(OH)2; InF2; CO2; RbCl2; CsSe; Be2O. *19. (a) Write Lewis formulas for the positive and negative ions inthese compounds: SrBr2; K2O; Ca3P2; PbCl2; Bi2O3. (b) Which ions do not have a noble gas configuration? *20. Write formulas for two cations and two anions that are isoelectronic with argon. *21. Write formulas for two cations and two anions that are isoelectronic with krypton. *22. Write formulas for two cations that have each of the following electron configurations in their highest occupied energylevel: (a) 3s23p6; (b) 4s24p6. *23. Write formulas for two anions that have each of the electron configurations listed in Exercise 22.

Lewis Formulas for Molecules and Polyatomic Ions
*28. What information about chemical bonding can a Lewis formula give for a compound or ion? What information about bonding is not directly represented by a Lewis formula? *29. Write Lewis formulas for thefollowing: H2; N2; Cl2; HCl; HBr. *30. Write Lewis formulas for the following: H2O; NH3; OH ; F . *31. Use Lewis formulas to represent the covalent molecules formed by these pairs of elements. Write only structures that satisfy the octet rule. (a) P and H; (b) Se and Br; (c) N and Cl; (d) Si and Cl. *32. Use Lewis formulas to represent the covalent molecules formed by these pairs of elements. Write...