Essential University Physics, 3e (Wolfson) Chapter 36 Atomic Physics
3 6. 1 Co nc e pt ua lQue s t i o ns 1) If two electrons in an atom have hav e the same energy, then they must have the same four quantum numbers. A) true B) false C) They cannot both have the same energy. Answer: B ar: 1
!) If two electrons in the same atom have h ave the same four quantum numbers, then they must have the same energy e nergy.. A) true B) false C) They cannot both have the same four quantum numbers. Answer: C ar: 1
") Consi#er the four quantum numbers of an electron in an atom, n, l , ml , an# m s. The energy of an electron in an isolate# atom #e$en#s on A) n only. B) n an# l only. only. C) n, l , an# ml only. %) l , ml , an# m s only. &) all four quantum numbers. Answer: A ar: 1
') (or each value of the $rinci$al quantum number n, what are the $ossible values of the electron s$in quantum number m s *There may be more than one correct choice.) A) + B) 1-! C) 1-! %) "-! &) "-! Answer: B, C ar: 1
/) 0hich of the following are characteristics of laser light *There may be more than one correct choice.) A) It is coherent. B) It is $ro#uce# by an inverte# $o$ulation of atoms. C) It contains a full s$ectrum of wavelengths. Answer: A, B ar: 1 1 Co$yright !+12 3earson &#ucation, Inc.
3 6 . 2 Pr o bl e ms 1) An electron in a hy#rogen atom is in the n 4 5 shell. 6ow many $ossible values of the orbital quantum number l coul# it have A) 2 B) 5 C) 1/ %) "" &) 78 Answer: B ar: 1
!) An electron in a hy#rogen atom has orbital quantum number l 4 5. 6ow many $ossible values of the magnetic quantum number ml coul# it have A) 2 B) 5 C) 1/ %) "" &) 78 Answer: C ar: 1
") An electron in a hy#rogen atom has $rinci$al quantum number n 4 '. 6ow many $ossible values of the orbital quantum number l coul# it have A) 8 B) 7 C) " %) ' &) 1+ Answer: % ar: 1
') An electron in a hy#rogen atom has orbital quantum number l 4 '. 6ow many $ossible values of the magnetic quantum number ml coul# it have A) ' B) 1+ C) / %) 7 &) " Answer: % ar: 1
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/) If the orbital quantum number is l 4 ', which one of the following is a $ossible value for the $rinci$al quantum number n A) 1 B) ! C) " %) ' &) 8 Answer: & ar: 1
2) If the $rinci$al quantum number of an electron is n 4 /, which one of the following is 9T an allowe# magnetic quantum number ml for the electron A) + B) ! C) " %) ' &) / Answer: & ar: 1
5) If an electron has s$in quantum number m s 4
what is the $ossible value for the orbital
quantum number l of the electron A) + B) 1 C) ! %) 11 &) All of the above numbers are $ossible. Answer: & ar: 1
8) In the groun# state, the quantum numbers *n, l , ml , m s) for hy#rogen are, res$ectively A) 1, 1, 1, 1 B) 1, +, +, + C) 1, +, +, ; %) 1, 1, 1, ; &) 1, 1, +, ; Answer: C ar: 1
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7) The bin#ing energy of the hy#rogen atom in its groun# state is 1".2 e. 0hat is the energy when it is in the n 4 / state A) !.5! e B) !.5! e C) +./'' e %) +./'' e &) 28 e Answer: % ar: 1
1+) 0hat is the energy of an inci#ent $hoton that is
11) 6ow fast must a hy#rogen atom be traveling for its >inetic energy to be g) A) ''.! >m-s B) !1.5 >m-s C) 22./ >m-s %) 11" >m-s &) /1.+ >m-s Answer: A ar: 1
1!) 0hat is the minimum s$ee# nee#e# by a groun#state hy#rogen atom for its >inetic energy to be enough to ionie the atom in a collision *1 e 4 1.2+ ? 1+17 @, m6 m $roton 4 1.25 ? 1+ !5 >g) A) ''.! >m-s B) !1.5 >m-s C) 22./ >m-s %) 11" >m-s &) /1.+ >m-s Answer: & ar: 1
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1") The normalie# wave function for a hy#rogen atom in the 1 s state is given by ψ *r ) 4 er/α0 where α+ is the Bohr ra#ius, which is equal to /.!7 ? 1+11 m. 0hat is the $robability of fin#ing the electron at a #istance greater than 5.8 α+ from the $roton A) !." ? 1+/ B) 1.! ? 1+/ C) 1.5 ? 1+/ %) '.2 ? 1+/ &) "./ ? 1+/ Answer: A ar: 1
1') 0hat is the greatest magnitu#e of the orbital angular momentum L for an electron in a state with $rinci$al quantum number A) '.'5 B) '.7+ C) / %) /.'8 Answer: A ar: /
1/) 0hat is the greatest total angular momentum J for an electron in the n 4 ! shell A) 1.7 B) !./ C) +./+ %) "./ &) 1./ Answer: A ar: 1
12) The magnitu#e of the orbital angular momentum L of an electron in a certain atom is equal to ".'2'ħ. 0hat is the orbital quantum number l of the electron A) 1 B) ! C) " %) ' &) / Answer: C ar: 1
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15) The magnitu#e of the orbital angular momentum L of an electron in a certain atom is equal to ".'2'ħ. 0hich one of the following numbers coul# be the $rinci$al quantum number n of the electron A) + B) 1 C) ! %) " &) ' Answer: & ar: 1
18) The magnitu#e of the orbital angular momentum L of an electron in a certain atom is equal to ".'2'ħ. 0hich of the following angles coul# 9T be the angle between the orbital angular momentum vector of the electron an# an arbitrary z-#irection A) 1+5 B) 7+.+ C) 5".! %) /'.5 &) +.++ Answer: & ar: 1
17) 6ow many electrons can be foun# with $rinci$al quantum number atom A) 18 B) 2 C) !+ %) 7 Answer: A
in a suitably heavy
ar: "
!+) An atom has com$letely fille# inner shells an# a single valence electron in an e=cite# p state. The fille# inner shells have an orbital momentum equal to ero. 0hat is the magnitu#e of the orbital angular momentum L of the atom A) 1.+ħ B) 1.!ħ C) 1.'ħ %) 1.5ħ &) !.+ħ Answer: C ar: 1
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!1) An atom has com$letely fille# inner shells an# a single valence electron in an e=cite# p state. The fille# inner shells have an orbital momentum equal to ero. A magnetic fiel# is a$$lie#, #efining the z-a=is along the fiel#. 0hich of the following sets of angles are $ossible angles between the magnetic fiel# an# the orbital angular momentum A) '/ B) 7+ C) '/, 7+ %) '/, 1"/ &) '/, 7+, 1"/ Answer: & ar: 1
!!) The only ADI% electron state an# shell #esignation among the following is A) 1 p, K. B) ! s, K. C) 1 s, L. %) ! p, L. &) " f , M. Answer: % ar: 1
!") The only I9ADI% electron state an# shell #esignation among the following is A) 1 s, K. B) ! s, L. C) !d , L. %) " s, M. &) "d , M. Answer: C ar: 1
!') The correct groun# state electron configuration of boron, which has / electrons, is A) 1 s!! s!! p. B) 1 s!! s!! p". C) 1 s!1 p!! s. %) 1 s!! p!" s. &) 1 s!! p". Answer: A ar: 1
!/) Consi#er the n 4 7 shell. *a) 0hat is the largest value of the orbital quantum number, l , in this shell *b) 6ow many electrons can be $lace# in this shell Answer: *a) 8 *b) 12! ar: 7
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!2) An atom with / electrons is in its groun# state. 6ow many electrons are in its outermost shell Answer: " ar: 8
!5) 6ow many electrons #oes it ta>e to fill the d subshell A) 1+ B) 2 C) 1' %) ' &) 8 Answer: A ar: 1
!8) 6ow many $ossible sets of quantum numbers *electron states) are there in the / f subshell A) ! B) 2 C) 8 %) 1+ &) 1' Answer: & ar: 1
!7) A neutral atom has an electron configuration of 1 s!! s!! p2" s!" p!. 6ow many $rotons #oes it have in its nucleus A) / B) 11 C) 1' %) !+ &) !2 Answer: C ar: 1
"+) 0hat is the electron configuration for groun# state Di, which has " electrons A) 1 s" B) 1 s1! s! C) 1 s!! s1 %) 1 s!1 p1 &) 1 s11 p! Answer: C ar: 1
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"1) 0hat is the correct electronic configuration for groun# state carbon, which has 2 electrons A) 1 s!! s!! p! B) 1 s1! p1 C) 1 s1! s!! p1 %) 1 s1! s1! p1 &) 1 s!! s!! p' Answer: A ar: 1
"!) 0hat is the correct electronic configuration for the groun# state so#ium atom, which has 11 electrons A) 1 s1! s!" p2! s! B) 1 s!! s1" p2! s! C) 1 s1! s!! p2 %) 1 s!! s!! p2" s! &) 1 s!! s!! p2" s1 Answer: & ar: 1
"") A collection of atoms has !+E of the sam$le in a state
above the groun# state. If these emit coherent ra#iation, what is the wavelength of the laser light $ro#uce# *c 4 ".++ ? 1+8 m-s, h 4 2.2!2 ? 1+"' @ F s, 1 e 4 1.2+ ? 1+ 17 @) A) !1+ nm B) 71 nm C) "'+ nm %) "' nm Answer: A ar: "1
"') 6ow many $hotons $er secon# emerge from a laser of $ower *c 4 ".++ ? 1+8 m-s, h 4 2.2!2 ? 1+"' @ F s) A) 2.+7 ? 1+1/ $hotons-s B) /.+" ? 1+1! $hotons-s C) ".+5 ? 1+1/ $hotons-s %) ".+5 ? 1+1" $hotons-s Answer: A ar: "8
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with wavelength
"/) Gou nee# 1' 0 of infrare# laser light $ower with wavelength 1!5+ nm to b ore a hole in a #iamon#. 6ow many #ownwar# atomic transitions $er secon# must occur in the laser if all of them result in light #irecte# onto the #iamon# *c 4 ".++ ? 1+8 m-s, h 4 2.2!2 ? 1+"' @ F s) A) 8.7 ? 1+17 B) 8.7 ? 1+18 C) /.7 ? 1+17 %) !.5 ? 1+18 Answer: A ar: 1
"2) The wavelength of a ruby laser is 27'." nm. 0hat is the energy #ifference between the two energy states involve# in laser action *c 4 !.7757 ? 1+8 m-s, h 4 2.2!2 ? 1+"' @ F s, 1 e 4 1.2+!! ? 1+17 @) A) 1./"5 e B) 1.2'2 e C) 1.582 e %) 1.81! e &) "./5! e Answer: C ar: 1
"5) In a ruby laser, an electron
"8) An s state *l 4 +) energy level is s$lit into two levels by an a$$lie# magnetic fiel#. A $hoton of microwave ra#iation having frequency 2+ H6 in#uces a transition between the two levels. 0hat is the magnitu#e of the a$$lie# magnetic fiel# *h 4 2.2!2 ? 1+"' @ F s, Bohr magneton 4 μB 4 7.!5 ? 1+!' @-T) A) !.1 T B) +."' T C) 1.! T %) !.8 T &) 1" T Answer: A ar: /+
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