Updated Nov.16/04
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NUMERICAL ANSWERS TO ASSIGNED TUTORIAL PROBLEM SETS FOR CHEM205
FROM KOTZ & TREICHEL'S CHEMISTRY & CHEMICAL REACTIVITY
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NOTE: none of the answers from Ch.7 have been verified
NOTE: "^" means "raised to the power of..." to indicate scientific notation...
NOTE: I cannot represent superscripts/subscripts here -- so...for polyatomic ions,
I have left a space between the ion's formula and its charge
Ch. Q# Answer Units SFs Comments
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7 14 n = principle Q.N. --> Energy & size
n = 1,2,3,...
l = angular momentum Q.N. --> shape of subshells
l = 0,1,2,3,...,n-1
m(l) = magnetic Q.N. --> orientation...specifies
exactly which orbital in subshell e- occupies
m(l) = -l to +l in integer increments
i.e., 0, +/-1, +/-2, +/-3,...+/-l
7 21a red, orange, yellow
21b blue
21c blue
7 23a 261 m 3 corresponds to 0.863 wavelengths
23b 3.06 m 3 corresponds to 73.6 wavelengths
7 25 4.8x10^-19 J/photon 2 wavelength 4.1x10^-7m; frequency 7.3x10^14 s-1
7 29a radar (least E per photon)
29b microwaves
29c red light
29d ultraviolet radiation
29e gamma-rays (most E per photon)
7 31 3.7x10^-19 J/photon 2 insufficient E (all radiation of >540 nm wavelength)
7 33a infrared region
33b none are shown in Fig.7.9 (none are in visible region)
33c highest E line has shortest wavelength, 837.761 nm
33d 2.29531x10^-19 J/photon 6
7 37a n=3 to n=2
37d n=3 to n=5
7 43 5.6x10^-12 m 2
7 45 1.41x10^-33 m 3 from speed = 313 m/s
7 47a a 4d orbital
47b n=5, l=0 --> a single s orbital
n=5, l=1 --> set of 3 p orbitals
n=5, l=2 --> set of 5 d orbitals
n=5, l=3 --> set of 7 f orbitals
n=5, l=4 --> set of 9 g orbitals
total of 5^2=25 orbitals in n=5 shell
47c an f subshell has 7 orbitals: m(l) = 0, +/-1, +/-2, +/-3
7 53a incorrect; when n=3, max value of l = 2
53b incorrect; when l=3, can have m(l) = 0, +/-1, +/-2, +/-3
7 57 2f and 1p are incorrect; not allowed l values for given n value
7 67 319 kJ/mol 3 energy of a mole of 375nm photons
7 69 5.9x10^4 photons 2 for photons of 4.2x10^19 J each
7 73 1s, 2s, 2p, 3s, 3p, 3d, 4s
7 77 Modern view of atom: based on e- simultaneously behaving as
wave & particle. Atomic structure described using WAVE description
of electron to define regions around nucleus where have highest
probability of finding electrons of specified energies.
7 79 (a) and (b)
7 83 8.0x10^25 photons 2 note: this question on heat transfer isn't really fair for Chem205
from 130J absorbed by eye; & 1.7x10^-24 J/photon of 0.120 m radiation
7 87a size, E and shape
87b 0, 1, 2
87c f
87d 4; 2; -2
87e p: l=1, 1 nodal plane; d: l=2, 2 nodal planes
87f f
87g 2d, 3f
87h n=2, l=1, m(l)=2 is not valid (invalid m(l) value)
87i (i) 3; (ii) 9; (iii) none; (iv) 1
7 87