7-9 suggested book problems PDF

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Tro Chapter 7 Review Questions: 1-4, 27-30, 32 Problems by Topic: 35, 39, 43, 51, 55, 59, 61, 67, 69, 71 Cumulative Problems: 73, 75 1. Why is the quantum-mechanical model of the atom important for understanding chemistry?

2. What is light? How fast does it travel in a vacuum?

3. Define the wavelength and amplitude of a wave. How are these related to the energy of the wave?

4. Define the frequency of electromagnetic radiation. How is frequency related to wavelength?

27. What are the possible values of the principal quantum number n? What does the principal quantum number determine?

28. What are the possible values of the angular momentum quantum number l? What does the angular momentum quantum number determine?

29. What are the possible values of the magnetic quantum number ml? What does the magnetic quantum number determine?

30. List all the orbitals in each principal level. Specify the three quantum numbers for each orbital.

n=1 n=2 n=3 n=4

32. Make sketches of the general shapes of the s, p, and d orbitals.

35. The distance from the sun to Earth is 1.496×108 km. How long does it take light to travel from the sun to Earth?

39. Calculate the frequency of each wavelength of electromagnetic radiation. 632.8 nm (wavelength of red light from helium–neon laser)

503 nm (wavelength of maximum solar radiation)

0.052 nm (a wavelength contained in medical X-rays)

43. A laser pulse with wavelength 532 nm contains 3.85 mJ of energy. How many photons are in the laser pulse?

51. What is the de Broglie wavelength of an electron traveling at 1.35×10 5 m/s?

55. An electron has an uncertainty in its position of 552 pm. What is the uncertainty in its velocity?

59. What are the possible values of l for each value of n? 1 2 3 4 61. Which set of quantum numbers cannot specify an orbital? n=2, l=1, ml=−1 n=3, l=2, ml=0 n=3, l=3, ml=2 n=4, l=3, ml=0 67. According to the quantum-mechanical model for the hydrogen atom, which electron transitions produces light with the longer wavelength: 2p→1s or 3p→1s?

69. Calculate the wavelength of the light emitted when an electron in a hydrogen atom makes each transition and indicate the region of the electromagnetic spectrum (infrared, visible, ultraviolet, etc.) where the light is found. n=2→n=1

n=3→n=1

n=4→n=2 n=5→n=2

71. An electron in the n=7 level of the hydrogen atom relaxes to a lowerenergy level, emitting light of 397 nm. What is the value of n for the level to which the electron relaxed?

73. Ultraviolet radiation and radiation of shorter wavelengths can damage biological molecules because these kinds of radiation carry enough energy to break bonds within the molecules. A typical carbon–carbon bond requires 348 kJ/mol to break. What is the longest wavelength of radiation with enough energy to break carbon–carbon bonds?

75. An argon ion laser puts out 5.0 W of continuous power at a wavelength of 532 nm. The diameter of the laser beam is 5.5 mm. If the laser is pointed toward a pinhole with a diameter of 1.2 mm, how many photons travel through the pinhole per second? Assume that the light intensity is equally distributed throughout the entire cross-sectional area of the beam. (1 W=1 J/s)

Tro Chapter 8 Review Questions: 7, 9, 16, 18, 21, 32, 33, 35, 37 Problems by Topic: 41, 45, 51, 53, 57, 61, 63, 65, 67, 71, 73, 78, 79 Cumulative Problems: 99 7. What is an electron configuration? Give an example.

9. What is shielding? In an atom, which electrons tend to do the most shielding (core electrons or valence electrons)?

16. What are valence electrons? Why are they important?

18. Explain why the s block in the periodic table has only two columns while the p block has six.

21. Describe the relationship between an element’s row number in the periodic table and the highest principal quantum number in the element’s electron configuration. How does this relationship differ for main-group elements, transition elements, and inner transition elements?

32. Describe the relationship between the radius of a cation and that of the atom from which forms

the radius of an anion and that of the atom from which it forms

33. What is ionization energy? What is the difference between first ionization energy and second ionization energy?

35. What are the exceptions to the periodic trends in first ionization energy? Why do they occur?

37. What is electron affinity? What are the observed periodic trends in electron affinity?

41. Write the full electron configuration for each element. Si O K Ne

45. Use the periodic table to write an electron configuration for each element. Represent core electrons with the symbol of the previous noble gas in brackets. P Ge Zr I 51. Determine the number of valence electrons in an atom of each element. Ba Cs Ni S 53. Which outer electron configuration would you expect to belong to a reactive metal? To a reactive nonmetal? ns2 ns2np6 ns2np5 ns2np2 57. Which experience a greater effective nuclear charge: the valence electrons in beryllium or the valence electrons in nitrogen? Why?

61. Choose the larger atom from each pair. Al or In Si or N P or Pb C or F 63. Arrange these elements in order of increasing atomic radius: Ca, Rb, S, Si, Ge, F.

65. Write the electron configuration for each ion. O2− Br− Sr2+ Co3+ Cu2+

67. Write orbital diagrams for each ion and indicate whether the ion is diamagnetic or paramagnetic. V5+ Cr3+ Ni2+ Fe 3+ 71. Arrange this isoelectronic series in order of decreasing radius: F −, O2−, Mg2+, Na+. 73. Choose the element with the higher first ionization energy from each pair. Br or Bi Na or Rb As or At P or Sn 78. Consider this set of ionization energies. IE1 = 578 kJ/mol IE2 = 1820 kJ/mol IE3 = 2750 kJ/mol IE4 = 11,600 kJ/mol To which third-period element do these ionization values belong?

79. Choose the element with the more negative (more exothermic) electron affinity from each pair. Na or Rb B or S C or N Li or F 99. Consider these elements: N, Mg, O, F, Al. Write the electron configuration for each element.

Arrange the elements in order of decreasing atomic radius. Arrange the elements in order of increasing ionization energy. Use the electron configurations in part a to explain the differences between your answers to parts b and c.

Chapter 9 Review Questions: 3, 4, 12, 15, 16, 19, 22, 23, 27 Problems by Topic: 37, 41, 43, 49, 53, 61, 63, 65, 67, 69, 71, 75, 77, 79 3. What are the three basic types of chemical bonds? What happens to electrons in the bonding atoms in each type?

4. How do you determine how many dots to put around the Lewis symbol of an element?

12. How does lattice energy relate to ionic radii? To ion charge?

15. In a covalent Lewis structure, what is the difference between lone pair and bonding pair electrons?

16. In what ways are double and triple covalent bonds different from single covalent bonds?

19. What is electronegativity? What are the periodic trends in electronegativity?

22. What is a dipole moment?

23. What is the magnitude of the dipole moment formed by separating a proton and an electron by 100 pm? 200 pm?

27. Do resonance structures always contribute equally to the overall structure of a molecule? Explain.

37. Write the Lewis symbol for each atom or ion. Al Na+ Cl

Cl− 41. Use Lewis symbols to determine the formula for the compound that forms between each pair of elements. Sr and Se

Ba and Cl

Na and S

Al and O

43. Explain the trend in the lattice energies of the alkaline earth metal oxides.

49. Use covalent Lewis structures to explain why each element (or family of elements) occurs as diatomic molecules. hydrogen

the halogens

oxygen

nitrogen 53. Write the Lewis structure for each molecule. SF2

SiH4

HCOOH (both O bonded to C)

CH3SH (C and S central)

61. Write the Lewis structure for each molecule or ion. N2H2

N2H4

C2H2

C2H4

63. Write a Lewis structure that obeys the octet rule for each molecule or ion. Include resonance structures if necessary and assign formal charges to each atom. SeO2

CO32−

ClO− NO2−

65. Use formal charge to identify the better Lewis structure.

67. How important is the resonance structure shown here to the overall structure of carbon dioxide? Explain.

69. Draw the Lewis structure (including resonance structures) for the acetate ion (CH3COO−). For each resonance structure, assign formal charges to all atoms that have formal charge.

71. What are the formal charges of the atoms shown in red?

75. Write the Lewis structure for each ion. Include resonance structures if necessary and assign formal charges to all atoms. If necessary, expand the octet on the central atom to lower formal charge. PO43−

CN−

SO32−

ClO2−

77. Write Lewis structures for each molecule or ion. Use expanded octets as necessary. PF5

l3−

SF4

GeF4

79. Order these compounds in order of increasing carbon–carbon bond strength and in order of decreasing carbon–carbon bond length: HCCH, H2CCH2, H3CCH3....