Essential University Physics, 3e (Wolfson) 3e (Wolfson) Chapter 37 Molecules and Solids
3 7. 1 Co nc e pt ua lQue s t i o ns 1) Covalent bonding is due to A) the sharing of electrons between atoms. B) the transfer of electrons between atoms. C) atoms bonding to hydrogen molecules. D) atoms bonding to oxygen molecules. Answer: A Var: 1
) !onic bonding is due to A) the sharing of electrons between atoms. B) the transfer of electrons between atoms. C) atoms bonding to hydrogen molecules. D) atoms bonding to oxygen molecules. Answer: B Var: 1
") A rotating diatomic molecule has rotational #uantum number l . $he energy D!%%&'&(C& between adacent energy levels A) increases as l increases. increases. B) decreases as l increases. increases. C) is the same for all changes in l . D) is inde*endent of l . Answer: A Var: 1
+) A rotating rotating diatomic molecule in its l , , 1 #uantum state has energy E energy E . -hat is the energy of the same molecule in its l , , #uantum state A) E B) " E C) + E D) / E &) 0 E Answer: B Var: 1
) A vibrating diatomic molecule has vibrational #uantum number n. $he energy D!%%&'&(C& between adacent energy levels A) increases as n increases. B) decreases as n increases. C) is the same for all changes in n. D) is inde*endent of n. Answer: D Var: 1 1 Co*yright 2 31/ 4earson &ducation5 !nc.
/) A vibrating diatomic molecule in its ground state has energy E . -hat is the energy of the same molecule in its second &6C!$&D state A) E B) E C) " E D) E &) 7 E Answer: D Var: 1
8) A p9ty*e semiconductor has a net *ositive charge. A) $rue B) %alse Answer: B Var: 1
0) An unfilled electron state in the valence band is called A) a hole. B) an em*ty electron. C) a conduction electron. D) a *ositron. &) an em*ty *ositron. Answer: A Var: 1
7) !n a p9ty*e semiconductor5 a hole is A) a donor atom. B) an extra electron su**lied by a donor atom. C) an extra *roton su**lied by a donor atom. D) a missing atom in the crystalline structure. &) a region where an electron is missing. Answer: & Var: 1
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3 7 . 2 Pr o bl e ms 1) A diatomic has a moment of inertia of 8.8" 139+ ;g< m. -hat is its rotational energy in the #uantum state characteri=ed by l , >h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 1 eV , 1./3 13917 ?) A) .8 @eV B) 8.3 @eV C) 08 @eV D) 8. @eV &) 08.1 @eV Answer: B Var: 1
) A diatomic molecule has ./ 139 eV of rotational energy in the l , #uantum state. -hat is its rotational energy in the l , 1 #uantum state A) ".+ @eV B) +.1 @eV C) ." @eV D) 8.0 @eV &) 0.8 @eV Answer: & Var: 1
") A diatomic molecule has 10 139 eV of rotational energy in the l , #uantum state. -hat is its rotational energy in the l , 3 #uantum state A) 73 @eV B) /3 @eV C) "3 @eV D) 1 @eV &) 3 eV Answer: & Var: 1
+) $he s*acing of the atoms >treated as *oint masses) in the molecule is 8.+ x 13911 m. -hat is the energy of the l , 1 rotational level >1 eV , 1./3 13 917 ?5 h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 m m *roton , 1./8 1398 ;g) A) 3.373 eV B) 3.383 eV C) 3.3+ eV D) 3.3"3 eV &) 3.31 eV Answer: & Var: 1
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) &stimate the rotational energy >in eV) for a diatomic hydrogen molecule in the l , #uantum state. >$he e#uilibrium se*aration for the molecule is 3.38+ nm.) >1 eV , 1./3 13917 ?5 h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 m m *roton , 1./8 1398 ;g) A) 3.311 eV B) 3.3/ eV C) 3.3" eV D) 3.3+/ eV &) 3.3 eV Answer: D Var: 1
/) $he moment of inertia of a fluorine >
) molecule is
-hat is the rotational
energy of a fluorine molecule for the l , 17 state >h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 1 eV , 1./3 13917 ?) A) +. 139 eV B) .1 139" eV C) +./ 139 eV D) .1 139 eV &) ./ 139 eV Answer: A Var: "
8) A certain molecule has .33 eV of rotational energy in the l , 1 state. !n the l , + state5 what would its rotational energy be A) 0.33 eV B) 1/.3 eV C) 3.3 eV D) "3.3 eV &) ".3 eV Answer: C Var: 1
0) -hen a certain diatomic molecule undergoes a transition from the l , to the l , " rotational level5 the emitted *hoton has wavelength
Calculate the moment of inertia of the
molecule. >c , ".33 130 ms5 e , 1./3 13917 C5 h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s) Answer: 1.+ 139+/ ;g < Var: 3
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7) $he vibrational fre#uency of an % molecule is 0.8 × 131" = and the reduced mass of the molecule is 1.07 × 1398 ;g. -hat is the ground state vibrational energy of an % molecule >1 eV , 1./3 13917 ?5 h , 1.3 139"+ ? < s5 h , /.// 139"+ ? < s) A) 3.1 eV B) 3.10 eV C) 3.+ eV D) 3."3 eV &) 3."/ eV Answer: B Var: 1
13) A diatomic molecule is vibrating in its first excited #uantum state above the ground state. !n that excited state5 its fre#uency is .3 13 1" =. -hat is the energy of the molecule in this state >h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 1 eV , 1./3 13917 ? A) 3.3+1 eV B) 3.30" eV C) 3.1 eV D) 3.1 eV &) 3.18 eV Answer: C Var: 1
11) A certain diatomic molecule emits a *hoton of energy 1.3 eV when it ma;es a transition from the n , 1 vibrational state to the next lower vibrational state. -hat is the fre#uency of vibration of the molecule >h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 1 eV , 1./3 13 917 ?) A) 1.7" 131+ = B) .73 131+ = C) +." 131+ = D) 1.0 131 = &) .8" 131 = Answer: B Var: 1
1) A certain diatomic molecule emits a *hoton of energy 1.3 eV when it ma;es a transition from the n , 1 vibrational state to the next lower vibrational state. !f the molecule made a transition from the n , state to the n , 1 state5 what would be the energy of the *hoton it would emit >h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 1 eV , 1./3 13917 ?) A) "./3 eV B) .+3 eV C) 1.3 eV D) 3./3 eV &) 3."3 eV Answer: C Var: 1 Co*yright 2 31/ 4earson &ducation5 !nc.
1") A**roximately how many states in the range from .3 eV to . eV are there in a co**er bar of volume ." cm" >h , /.// 139"+ ? < s5 h , 1.3 139"+ ? < s5 mel , 7.11 139"1 ;g5 1 eV , 1./3 13917 ?) A) .1 13 B) ". 13 C) 1./ 13 D) 0. 131 &) ". 131 Answer: C Var: 1
1+) $he energy ga* between the valence and conduction bands in a certain semiconductor is 1. eV. -hat is the threshold wavelength for o*tical absor*tion in this substance >c , ".33 130 ms5 1 eV , 1./3 13917 ?5 h , /.// 139"+ ? < s) A) 77 nm B) /"7 nm C) 77 nm D) 08" nm &) 77+ nm Answer: & Var: 1
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