Introduction to Chemistry, 4E (Russo) Chapter 4 the Modern Model of the Atom

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Introduction to Chemistry, 4e (Russo) Chapter 4 The Modern Model of the Atom

4.1 Multiple-Choice Questions

1) What is the main difference between "classical physics" and "quantum physics"? A) Quantum physics requires the speed of light to be a constant value. B) Classical physics requires that only certain, allowed values for energy be used. C) Quantum physics requires that only certain, allowed values for energy be used. D) Quantum physics can only describe the behavior of very small objects, like atoms and molecules. Answer: C Topic: Section 4.2

2) For the electron of a hydrogen atom, which of the following quantum "jumps" requires the most energy? A) from n = 3 to n = 4 B) from n = 2 to n = 3 C) from n = 4 to n = 5 D) from n = 1 to n = 2 Answer: D Topic: Section 4.4

3) Which feature of Bohr's atomic model is no longer accepted as true by today's scientists? A) that most of an atom's mass is located within the nucleus B) that electrons have only certain, allowed energy values C) that electrons orbit the nucleus in circular paths D) that each principal quantum level can hold a maximum of 2n2 electrons Answer: C Topic: Section 4.3

4) Which of the following subshells does not appear in the third shell? A) s B) p C) d D) f Answer: D Topic: Section 4.5

5) Which of the following subshells appear in the second shell? A) s B) s,p C) s, p, d D) p Answer: B Topic: Section 4.5

1 Copyright © 2011 Pearson Education, Inc. 6) The correct order of increasing energy in the following subshells is: A) 2p, 3s, 4s, 3p, 3d B) 2p, 3s, 3p, 4s, 3d C) 2p, 3s, 3p, 3d, 4s D) 2p, 3s, 3d, 3p, 4s Answer: B Topic: Section 4.5

7) How many electrons can be "stored" in a completely filled 4f sublevel? A) 14 B) 10 C) 7 D) 28 Answer: A Topic: Section 4.5

11) The total number of electrons that can be accommodated in 3d is ______. A) 5 B) 2 C) 6 D) 10 Answer: D Topic: Section 4.6

13) Which of the following anions will have the electronic configuration 1s22s22p63s23p6 ? A) K1- B) Cl1- C) S2- D) Br1- Answer: B Topic: Section 4.7

15) The likely formula of the compound formed between Ca and O is ______. A) Ca2O B) CaO2 C) Ca2O3 D) CaO Answer: D Topic: Section 4.7

16) Which of the following elements never obeys the octet rule? A) Hydrogen B) Nitrogen C) Carbon D) Chlorine Answer: A Topic: Section 4.7

17) Which is the correct electronic configuration for Se (atomic number 34) in the ground state? 2 Copyright © 2011 Pearson Education, Inc. A) 1s22s22p63s23p63d104s24p4 B) 1s22s22p63s23p63d104s04p6 C) 1s22s22p63s23p64s23d104p4 D) 1s22s22p63s23p63d104s03p6 Answer: C Topic: Section 4.5

19) Which of the following species does not match the electronic configuration 1s22s22p63s23p64s23d104p6 ? A) Br- B) Sr+2 C) As-3 D) Se+2 Answer: D Topic: Section 4.7

20) Which species has the following electronic configuration: 1s22s22p63s23p6 ? A) F- B) Mg+2 C) P-3 D) S- Answer: C Topic: Section 4.7

22) Which of the following does not have the neon electron configuration? A) S4+ B) Mg2+ C) O2- D) Al3+ Answer: A Topic: Section 4.7

23) The scientist credited with developing the current mathematical model of the atom is ______. A) Bohr B) Schrodinger C) Planck D) Rutherford Answer: B Topic: Section 4.8

25) Atoms in which of the following groups will likely gain three electrons? A) IIIA B) VA C) VIIA D) both A and B Answer: B Topic: Section 4.7

27) The relative ratio of atoms in the binary compound AlxOy is ______. A) x=2, y=3 B) x=3, y=2 C) x=5, y=2 D) x=2, y=5 Answer: A Topic: Section 4.7

28) The size of boron is ______than that of oxygen and ______than that of aluminum. A) smaller; larger B) larger; larger C) smaller; smaller D) larger; smaller Answer: D Topic: Section 4.6

29) Which orbital is dumbbell-shaped? A) 2s B) 3p C) 4d D) 5g Answer: B Topic: Section 4.8

30) Which orbital is a spherical shape? A) 2s B) 3p C) 4d D) 5f Answer: A Topic: Section 4.8

31) What is the number of outer shell electrons in fluorine? A) 2 B) 5 C) 7 D) 9 Answer: C Topic: Section 4.5

33) The valence shell ______. A) always contains eight electrons B) is the lowest energy shell in an atom C) is the outermost occupied shell in an atom D) is always the same for anions and cations Answer: C Topic: Section 4.7

34) Below are four pairs of atoms and ions. In which pair is the larger of the two species written first? A) S2- and S B) Cu2+ and Cu C) O and O2- D) Cr3+ and Cr Answer: A Topic: Section 4.7

35) The ion that has 14 protons and 18 electrons is ______. A) Si4+ B) Si4- C) N4+ D) N4- Answer: B Topic: Section 4.7

36) Which of the following has attained a noble gas electronic configuration? A) Si4+ B) Cl1+ C) Al3- D) Cr3+ Answer: A Topic: Section 4.7

37) Which color light is composed of photons having the largest energy? A) blue B) green C) yellow D) red Answer: A Topic: Section 4.1

38) Which type of electromagnetic radiation is composed of photons having the largest energy?

40) The elements of Group VIIIA are almost entirely non-reactive with any of the other chemical elements. Which of the following statements best explains this observed behavior? A) Group VIIIA elements comply with the octet rule. B) Group VIIIA elements are so rare that no one has ever studied their reactive properties in any detail. C) Group VIIIA elements are all gases, and gases are generally non-reactive. D) No explanation given here can explain why Group VIIIA elements do not react with any of the other chemical elements. Answer: A Topic: Section 4.7

41) What is the trend in atomic size in the series of Group IIA elements Be through Ra? A) Atomic size increases in this series. B) Atomic size decreases in this series. C) Atomic size remains unchanged in this series. D) Atomic size increases at first, then decreases in this series. Answer: A Topic: Section 4.6

42) Predict the formula of the compound produced in a reaction between barium (Ba) and oxygen (O). A) BaO2 B) BaO C) BaO2 D) Ba2O3 Answer: B Topic: Section 4.7

43) Predict the formula of the compound produced in a reaction between lithium (Li) and phosphorus (P). A) LiP B) Li2P3 C) LiP2 D) Li3P Answer: D Topic: Section 4.7

44) What is the wavelength (in meters) of radio waves that have a frequency of 89.9 MHz? (wavelength × frequency = speed of light; speed of light = 3 × 108 meters/sec.) A) 3.34 centimeters B) 2.70 × 1016 millimeters C) 0.300 meters D) 3.34 meters Answer: D 6 Copyright © 2011 Pearson Education, Inc. Topic: Section 4.1

45) Calculate the energy in joules of microwave radiation of wavelength 12.7 centimeters. (E = hν, h = 6.63 × 10-34 J sec; speed of light = wavelength × ν, speed of light = 3 × 108 meters/sec.) A) 4.87 × 1019 J B) 7.30 × 10-19 J C) 3.61 × 10-18 J D) 1.56 × 10-24 J Answer: D Topic: Section 4.1

46) In a single atom, what is the maximum number of electrons that can have quantum number n=4? A) 10 B) 14 C) 18 D) 32 Answer: D Topic: Section 4.3

47) The units of h (Planck's constant) are ______. A) J.s B) J/s C) m/s D) J/nm Answer: A Topic: Section 4.1

49) Which of the following elements is the smallest size chalcogen? A) H B) N C) O D) F Answer: C Topic: Section 4.8

50) Which of the following elements is the largest size halogen? A) He B) Br C) F D) Kr Answer: B Topic: Section 4.7

1) Bohr's atomic theory places an atom's electrons in discrete-energy circular paths around a central, positively charged nucleus. Answer: TRUE Topic: Section 4.3

3) The only possible way for an excited state electron to return to the ground state is to emit energy in the form of visible light. Answer: FALSE Topic: Section 4.1

4) Atoms tend to increase in size as one moves from left to right across a period. Answer: FALSE Topic: Section 4.6

6) The f-block represents a region on the periodic table which is 10 elements in width. Answer: FALSE Topic: Section 4.5

7) The p-block represents a region on the periodic table which is 6 elements in width. Answer: TRUE Topic: Section 4.5

8) The n = 5 principal energy level can hold a maximum of 25 electrons. Answer: FALSE Topic: Section 4.5

9) The s-type orbitals of any given principal energy level are always spherical in shape. Answer: TRUE Topic: Section 4.8

11) The atomic radius can be calculated by x-ray diffraction. Answer: TRUE Topic: Section 4.6

12) Modern scientists accept the notion that electrons are found in circular orbits around a central, positively charged nucleus. Answer: FALSE Topic: Section 4.8

14) Should an oxygen atom (O) gain two electrons, it would then have the same ground state electronic configuration as an atom of neon (Ne), thus satisfying the octet rule. Answer: TRUE Topic: Section 4.7

16) The atom size decreases as one proceeds from left to right across a period. Answer: TRUE Topic: Section 4.6

18) +1 is the only charge sodium ions normally have. Answer: TRUE Topic: Section 4.6

19) The element is defined by its atomic number. Answer: TRUE Topic: Section 4.1

20) If an element has a small electron affinity value it can easily lose an electron. Answer: FALSE Topic: Section 4.6

21) Halogens have large electron affinity values. Answer: TRUE Topic: Section 4.6

22) H+ has one electron. Answer: FALSE Topic: Section 4.7

23) The wavelength is the distance measured between two crests, but not between two troughs. Answer: FALSE Topic: Section 4.1

24) Carbon can assume both +4 and -4 charges. Answer: TRUE Topic: Section 4.7

25) The speed of light is about 186,000 miles per minute. Answer: FALSE Topic: Section 4.1

26) Shells get larger as the principal quantum number n increases. Answer: TRUE Topic: Section 4.8

27) The number of electrons in the valence shell of an atom is equal to the group number for the representative elements. Answer: TRUE Topic: Section 4.5

28) Once an atom gets excited, it may remain in that excited state indefinitely. Answer: FALSE Topic: Section 4.4

30) The 95% boundary indicates the area where 95% of the time the electron may be found. Answer: TRUE Topic: Section 4.8

31) Both the energy and the wavelength of electromagnetic radiation are related by the constants c, the speed of light, and Planck's constant, h. Answer: TRUE Topic: Section 4.1

34) Microwave is radiation of a lower energy than that of visible light. Answer: TRUE Topic: Section 4.1

35) The red light is the element that possesses the lowest frequency of the visible region of the electromagnetic spectrum. Answer: TRUE Topic: Section 4.1

36) The frequency of infrared radiation that has a wavelength of 1.5 × 103 nm is 2.0 × 107 sec-1 (given: speed of light = 3.0 × 108 m/sec). Answer: FALSE Topic: Section 4.1

37) The wavelengths in infrared radiation are larger than those of the ultraviolet region. Answer: TRUE Topic: Section 4.1

4.3 Short Answer Questions

1) Write the complete electronic ground state configuration for tellurium (Te). Make sure the terms in your answer are listed in order of increasing energy. Answer: Two possible, equally correct answers: the abbreviated [Kr] 5s24d105p4, or the complete 1s22s22p63s23p64s23d104p65s24d105p4 . Topic: Section 4.5

2) Which element is the more reactive, sodium (Na) or potassium (K)? Answer: Potassium (K), as it possesses a more accessible, single valence electron by virtue of its larger size. This lone electron is found farther from the nucleus in potassium than sodium, and is easier to remove, making it more reactive. Topic: Section 4.7

3) Write the complete electronic ground state configuration of the Se2- ion. Which other element (if any) shares this electronic configuration? Answer: Se : 1s22s22p63s23p64s23d104p6. This is the same electronic configuration as the element krypton (Kr). 10 Copyright © 2011 Pearson Education, Inc. Topic: Section 4.7

4) List the sublevels of the n = 3 principal energy level, and state the maximum number of electrons contained within each of these sublevels. Answer: n = 3: 3s, containing 2 electrons 3p, containing 6 electrons 3d, containing 10 electrons Topic: Section 4.5

4.4 Matching Questions

Match each element with the most likely valence charge of its ion in the list below.

A) (-1) B) (-2) C) (+2) D) (+3) E) (-3) F) (+1) G) zero H) (+4 or -4)

1) Li Topic: Section 4.7

2) O Topic: Section 4.7

3) S Topic: Section 4.7

4) C1 Topic: Section 4.7

5) Si Topic: Section 4.7

6) Ba Topic: Section 4.7

7) N Topic: Section 4.7

8) Br Topic: Section 4.7

9) K Topic: Section 4.7

11) Al Topic: Section 4.7

12) P Topic: Section 4.7

13) H Topic: Section 4.7

14) I Topic: Section 4.7

15) He Topic: Section 4.7

Answers: 1) F 2) B 3) B 4) A 5) H 6) C 7) E 8) A 9) F 10) G 11) D 12) E 13) F 14) A 15) G

Match the following species with the corresponding electronic configuration from the list below.

A) 1s22s22p63s23p6 B) 1s22s22p63s23p1 C) 1s22s22p63s2 D) 1s22s22p63s23p5 E) 1s22s22p63s23p4 F) 1s22s22p6 G) 1s22s22p63s23p3 H) 1s22s22p63s23p2

16) Mg2+ Topic: Section 4.7

17) Ca2+ Topic: Section 4.7

18) Al Topic: Section 4.7

19) P Topic: Section 4.7

20) Si4+ Topic: Section 4.7

21) Si4-

22) C15+ Topic: Section 4.7

23) S Topic: Section 4.7

24) S+4 Topic: Section 4.7

25) S6+ Topic: Section 4.7

26) S2- Topic: Section 4.7

27) N3- Topic: Section 4.7

28) Si Topic: Section 4.7

29) C1 Topic: Section 4.7

Answers: 16) F 17) A 18) B 19) G 20) F 21) A 22) C 23) E 24) C 25) F 26) A 27) F 28) H 29) D

Match the outermost occupied orbital(s) with the corresponding element from the list below.

A) Sr B) Dy C) Th D) Cu E) Xe F) Br G) Mn

30) 5s2 Topic: Section 4.5

31) 4p5 Topic: Section 4.5

32) 3d5 Topic: Section 4.5

34) 5p6 Topic: Section 4.5

35) 6s24f10 Topic: Section 4.5

36) 7s26d2 Topic: Section 4.5

Answers: 30) A 31) F 32) G 33) D 34) E 35) B 36) C

Classify each of the following as ground state, excited state, or impossible electronic configurations.

A) Excited State B) Impossible state C) Ground State

37) 1s22s22p63s13p3 Topic: Section 4.5

38) 1s22s22p63s23p8 Topic: Section 4.5

39) 1s22s22p63s23p64s1 Topic: Section 4.5

40) 1s22s22p63s23p64s24p1 Topic: Section 4.5

41) 1s22s22p63s23p64s23d5 Topic: Section 4.5

42) 1s22s22p63s23p64s13d104p1 Topic: Section 4.5

43) 1s22s22p63s23p64s23d12 Topic: Section 4.5

Answers: 37) A 38) B 39) C 40) A 41) C 42) A 43) B

Match the scientist with his contribution from the list below.

A) Is the father of quantum physics B) Suggested the existence of a tiny, massive nucleus C) First described the quantum theory of energy D) Proposed the quantized energy of electrons

45)Ernest Rutherford Topic: Section 4.8

46)Erwin Schrodinger Topic: Section 4.8

47)Max Planck Topic: Section 4.8

Answers: 44) C 45) B 46) A 47) D

Match every binary compound in the first column with the correct coefficient of x and y in the second column.

A) x = 1, y = 3 B) x = 4, y = 1 C) x = 2, y = 3 D) x = 1, y = 1 E) x = 1, y = 2 F) x = 3, y = 1 G) x = 3, y = 2 H) x = 3, y = 4 I) x = 2, y = 1 J) x = 1, y = 4

48) AlxCly Topic: Section 4.7

49) NaxSy Topic: Section 4.7

50) MgxOy Topic: Section 4.7

51) CaxNy Topic: Section 4.7

52) CxCly Topic: Section 4.7

53) LixCy Topic: Section 4.7

54) AlxSy Topic: Section 4.7

56) CxOy Topic: Section 4.7

57) LixNy Topic: Section 4.7

58) CxNy Topic: Section 4.7

59) BxFy Topic: Section 4.7

60) BaxCly Topic: Section 4.7

61) LixHy Topic: Section 4.7

Answers: 48) A 49) I 50) E 51) G 52) J 53) B 54) C 55) A 56) E 57) F 58) H 59) A 60) E 61) D