47374 06 p43-66sciences.unlv.edu/chemistry/hatchett/pdf/103/ch06solutions.pdf · c. d. one mol...
TRANSCRIPT
43
6Chemical Quantities
6.1 a.
b.
c.
6.2 a.
b.
c.
6.3 a.
b.
c.
6.4 a.
b.
c.
6.5 a.
b.
c.
1 atom O !16.00 amu1 atom O
"16.00 amu46.07 amu (formula mass)
6 atoms H !1.008 amu1 atom H
" 6.048 amu
2 atoms C !12.01 amu1 atom C
" 24.02 amu
6 atoms O !16.00 amu1 atom O
"96.00 amu
164.10 amu (formula mass)
2 atoms N !14.01 amu1 atom N
" 28.02 amu
1 atom Ca !40.08 amu1 atom Ca
" 40.08 amu
6 atoms F !19.00 amu1 atom F
"114.0 amu146.1 amu (formula mass)
1 atom S !32.07 amu1 atom S
" 32.07 amu
128 000 amu Sr !1 atom Sr
87.62 amu Sr " 1.46 ! 103 atoms Sr
6400 amu Kr !1 atom Kr
83.80 amu Kr " 76 atoms Kr
1.60 ! 104 amu Cu !1 atom Cu
63.55 amu Cu " 2.52 ! 102 atoms Cu
35 000 amu Ne !1 atom Ne
20.18 amu Ne " 1.7 ! 103 atoms Ne
2.95 amu Ag !1 atom Ag
107.9 amu Ag " 2.73 ! 102 atoms Ag
540 amu Al !1 atom Al
26.98 amu Al " 20 atoms Al
9.15 ! 1025 Cl atoms !35.45 amu1 Cl atom
" 3.24 ! 1027 amu
2.80 ! 103 P atoms !30.97 amu1 P atom
" 8.67 ! 104 amu
75 Ba atoms !137.3 amu1 Ba atom
" 1.030 ! 104 amu
6.24 ! 1020 F atoms !19.00 amu1 F atom
" 1.19 ! 1022 amu
1.50 ! 105 Cr atoms !52.00 amu1 Cr atom
" 7.80 ! 106 amu
25 O atoms !16.00 amu1 O atom
" 400.0 amu (4.000 ! 102 amu)
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44
Chapter 6
d.
6.6 a.
b.
c.
d.
6.7 a.
b.
3 atoms H !1.008 amu1 atom H
"3.024 amu
78.00 amu (formula mass)
3 atoms O !16.00 amu1 atom O
" 48.00 amu
1 atom Al !26.98 amu1 atom Al
" 26.98 amu
3 atoms O !16.00 amu1 atom O
"48.00 amu
126.05 amu (formula mass)
1 atom S !32.07 amu1 atom S
" 32.07 amu
2 atoms Na !22.99 amu1 atom Na
" 45.98 amu
2 atoms O !16.00 amu1 atom O
"32.00 amu
194.20 amu (formula mass)
4 atoms N !14.01 amu1 atom H
" 56.04 amu
10 atoms H !1.008 amu1 atom N
" 10.08 amu
8 atoms C !12.01 amu1 atom C
" 96.08 amu
3 atoms O !16.00 amu1 atom O
"48.00 amu92.09 amu (formula mass)
8 atoms H !1.008 amu1 atom H
" 8.064 amu
3 atoms C !12.01 amu1 atom C
" 36.03 amu
3 atoms O !16.00 amu1 atom O
"48.00 amu96.09 amu (formula mass)
8 atoms H !1.008 amu1 atom H
" 8.064 amu
1 atom C !12.01 amu1 atom C
" 12.01 amu
2 atoms N !14.01 amu1 atom N
" 28.02 amu
7 atoms O !16.00 amu1 atom O
"112.0 amu182.9 amu (formula mass)
2 atoms Cl !35.45 amu1 atom Cl
" 70.90 amu
6 atoms O !16.00 amu1 atom O
"96.00 amu
180.16 amu (formula mass)
12 atoms H !1.008 amu1 atom H
" 12.10 amu
6 atoms C !12.01 amu1 atom C
" 72.06 amu
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 44
c.
d.
6.8 a.
b.
c.
d.
6.9 The mole is a unit that contains particles (atoms, molecules of a covalent substance,ions, or formula units of an ionic substance).
6.10 Avogadro’s number is , which is the number of particles in a mole.
6.11 One mol of chlorine atoms contains atoms chlorine; 1 mol of chlorine moleculescontains molecules chlorine, which is or atomschlorine.
1.204 ! 10242 ! 6.022 ! 10236.022 ! 10236.022 ! 1023
6.022 ! 1023
6.022 ! 1023
2 atoms Cl !35.45 amu1 atom Cl
" 70.90 amu300.1 amu
6.048 amu6 atoms H !1.008 amu1 atom H
"
28.02 amu2 atoms N !14.01 amu1 atom N
"
195.1 amu1 atom Pt !195.1 amu1 atom Pt
"
8 atoms O !16.00 amu1 atom O
" 128.0 amu386.1 amu (formula mass)
2 atoms P !30.97 amu1 atom P
" 61.94 amu
3 atoms Zn !65.41 amu1 atom Zn
" 196.2 amu
4 atoms O !16.00 amu1 atom O
" 64.00 amu
132.15 amu (formula mass)
1 atom S !32.07 amu1 atom S
" 32.07 amu
8 atoms H !1.008 amu1 atom H
" 8.064 amu
2 atoms N !14.01 amu1 atom N
" 28.02 amu
3 atoms O !16.00 amu1 atom O
" 48.00 amu
100.09 amu (formula mass)
1 atom C !12.01 amu1 atom Ca
" 12.01 amu
1 atom Ca !40.08 amu1 atom Ca
" 40.08 amu
8 atoms O !16.00 amu1 atom O
" 128.0 amu310.1 amu (formula mass)
2 atoms P !30.97 amu1 atom P
" 61.94 amu
3 atoms Ca !40.08 amu1 atom Ca
" 120.2 amu
4 atoms O !16.00 amu1 atom O
"64.00 amu
151.92 amu (formula mass)
1 atom S !32.07 amu1 atom S
" 32.07 amu
1 atom Fe !55.85 amu1 atom Fe
" 55.85 amu
Chemical Quantities
45
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46
Chapter 6
6.12 1 mol of N atoms is atoms of N, whereas 1 mol of molecules is molecules of . There are two N atoms in an N2 molecule, so there would be twice as many Natoms in 1 mol of molecules as in 1 mol of N atoms.
6.13 a.
b.
c.
d.
6.14 a.
b.
c.
d.
6.15 One mol molecules contains 3 mol H atoms, 1 mol P atoms, and 4 mol O atoms.
a.
b.
c.
d.
6.16 1 mol molecules contains 6 mol C atoms, 10 mol H atoms, and 1 mol O atoms.
a.
b.
c.
d.
6.17 a.
b.
3 mol O !16.00 g O1 mol O
" 48.00 g O
159.7 g Fe2O3 (molar mass)
2 mol Fe !55.85 g Fe1 mol Fe
" 111.7 g Fe
1 mol Cl !35.45 g Cl1 mol Cl
"35.45 g Cl58.44 g NaCl (molar mass)
1 mol Na !22.99 g Na1 mol Na
" 22.99 g Na
0.185 mol (C3H5)2O !6 mol C
1 mol (C3H5)2O!
6.022 ! 1023 atoms C1 mol C
" 6.68 ! 1023 C atoms
0.185 mol (C3H5)2O !10 mol H
1 mol (C3H5)2O!
6.022 ! 1023 atoms H 1 mol H
" 1.11 ! 1024 H atoms
0.185 mol (C3H5)2O !1 mol O
1 mol (C3H5)2O" 0.185 mol O
0.185 mol (C3H5)2O !6 mol C
1 mol (C3H5)2O" 1.11 mol C
(C3H5)2O
2.00 mol H3PO4 !4 mol O
1 mol H3PO4!
6.022 ! 1023 atoms O1 mol O
" 4.82 ! 1024 O atoms
2.00 mol H3PO4 !1 mol P
1 mol H3PO4!
6.022 ! 1023 atoms P1 mol P
" 1.20 ! 1024 P atoms
2.00 mol H3PO4 !4 mol O
1 mol H3 PO4" 8.00 mol O
2.00 mol H3PO4 !3 mol H
1 mol H3PO4" 6.00 mol H
H3PO4
3.754 ! 1023 molecules C2H6 !1 mol C2H6
6.022 ! 1023 molecules C2H6" 0.6234 mol C2H6
7.8 ! 1021 atoms Cu !1 mol Cu
6.022 ! 1023 atoms Cu" 0.013 mol Cu
0.0180 mol CO2 !6.022 ! 1023 atoms CO2
1 mol CO2" 1.08 ! 1022 CO2 molecules
4.5 mol Li !6.022 ! 1023 atoms Li
1 mol Li" 2.7 ! 1024 Li atoms
8.50 ! 1024 molecules C2H5OH !1 mol C2H5OH
6.022 ! 1023 molecules C2H5OH" 14.1 mol C2H5OH
5.22 ! 1022 atoms Fe !1 mol Fe
6.022 ! 1023 atoms Fe" 0.0867 mol Fe
1.28 mol SO2 !6.022 ! 1023 molecules SO2
1 mol SO2" 7.71 ! 1023 SO2 molecules
0.500 mol C !6.022 ! 1023 atoms C
1 mol C" 3.01 ! 1023 C atoms
N2
N2
6.022 ! 1023N26.022 ! 1023
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 46
c.
d. One mol contains 2 mol Al, 3 mol S, and 12 mol O.
e.
f. One mol contains 16 mol C, 19 mol H, 3 mol N, 5 mol O, and 1 mol S.
6.18 a.
b.
3 mol O !16.00 g O1 mol O
" 48.00 g O
101.96 g (molar mass)
2 mol Al !26.98 g Al1 mol Al
" 53.96 g Al
4 mol O !16.00 g O1 mol O
" 64.00 g O
151.92 g (molar mass)
1 mol S !32.07 g S1 mol S
" 32.07 g S
1 mol Fe !55.85 g Fe1 mol Fe
" 55.85 g Fe
1 mol S !32.07 g S1 mol S
" 32.07 g S
365.5 g C16H19N3O5S
5 mol O !16.00 g O1 mol O
" 80.00 g O
3 mol N !14.01 g N1 mol N
" 42.03 g N
19 mol H !1.008 g H1 mol H
" 19.15 g H
16 mol C !12.01 g C1 mol C
" 192.2 g C
C16H19N3O5S
5 mol H !1.008 g H1 mol H
" 5.040 g H
188.18 g KC4H5O6 (molar mass)
6 mol O !16.00 g O1 mol O
" 96.00 g O
4 mol C !12.01 g C1 mol C
" 48.04 g C
1 mol K !39.10 g K1 mol K
" 39.10 g K
12 mol O !16.00 g O1 mol O
" 192.0 g O342.2 g Al2(SO4)3
3 mol S !32.07 g S1 mol S
" 96.21 g S
2 mol Al !26.98 g Al1 mol Al
" 53.96 g Al
Al2(SO4)3
1 mol N !14.01 g N1 mol N
" 14.01 g N
277.4 g C2OH23N (molar mass)
23 mol H !1.008 g H1 mol H
" 23.18 g H
20 mol C !12.01g C1 mol C
" 240.2 g C
Chemical Quantities
47
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48
Chapter 6
c.
d.
e.
f.
6.19 a.
b.
c.
8 mol O !16.00 g O1 mol O
" 128.0 g O262.9 g C3H6O3
2 mol P !30.97 g P1 mol P
" 61.94 g P
3 mol Mg !24.31 g Mg1 mol Mg
" 72.93 g Mg
3 mol O !16.00 g O1 mol O
" 48.00 g O90.08 g C3H6O3
6 mol H !1.008 g H1 mol H
" 6.048 g H
3 mol C !12.01 g C1 mol C
" 36.03 g C
2 mol Cl !35.45 g Cl1 mol Cl
" 70.90 g Cl2
4 mol O !16.00 g O1 mol O
" 64.00 g O
183.50 g (molar mass)
6 mol H !1.008 g H1 mol H
" 6.048 g H
4 mol C !12.01 g C1 mol C
" 48.04 g C
1 mol Zn !65.41 g Zn1 mol Zn
" 65.41 g Zn
3 mol O !16.00 g O1 mol O
" 48.00 g O96.09 g (molar mass)
1 mol C !12.01 g C1 mol C
" 12.01 g C
8 mol H !1.008 g H1 mol H
" 8.064 g H
2 mol N !14.01 g H1 mol N
" 28.02 g N
1 mol O !16.00 g O1 mol O
" 16.00 g O60.09 g (molar mass)
8 mol H !1.008 g H1 mol H
" 8.064 g H
3 mol C !12.01 g C1 mol C
" 36.03 g C
1 mol S !32.07 g S1 mol S
" 32.07 g S
183.19 g (molar mass)
3 mol O !16.00 g O1 mol O
" 48.00 g O
1 mol N !14.01 g N1 mol N
" 14.01 g N
5 mol H !1.008 g H1 mol H
" 5.040 g H
7 mol C !12.01 g C1 mol C
" 84.07 g C
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 48
d.
e.
f.
6.20 a.
b.
c.
d.
e.
f.
4 mol O !16.00 g O1 mol O
" 64.00 g O
183.00 g
1 mol Br !79.90 g Br1 mol Br
" 79.90 g Br
1 mol K !39.10 g K1 mol K
" 39.10 g K
9 mol O !16.00 g O1 mol O
" 144.0 g O319.4 g
3 mol C !12.01 g C1 mol C
" 36.03 g C
2 mol Ga !69.72 g Ga1 mol Ga
" 139.4 g Ga
4 mol O !16.00 g O1 mol O
" 64.00 g120.10 g
8 mol H !1.008 g H1 mol H
" 8.064 g H
4 mol C !12.01 g C1 mol C
" 48.04 g C
12 mol O !16.00 g O1 mol O
" 192.0 g O354.3 g
3 mol Cl !35.45 g Cl1 mol Cl
" 106.4 g Cl
1 mol Fe !55.85 g Fe1 mol Fe
" 55.85 g Fe
4 mol O !16.00 g O1 mol O
" 64.00 g136.09 g
1 mol P !30.97 g P1 mol P
" 30.97 g P
2 mol H !1.008 g H1 mol H
" 2.016 g H
1 mol K !39.10 g K1 mol K
" 39.10 g Mg
2 mol O !16.00 g O2
1 mol O " 32.00 g O2
2 mol F !19.00 g F1 mol F
" 38.00 g F
156.7 g SnF2
1 mol Sn !118.7 g Sn1 mol Sn
" 118.7 g Sn
2 mol Cl !35.45 g Cl1 mol Cl
" 70.90 g Cl98.95 g C2H4Cl2
4 mol H !1.008 g H1 mol H
" 4.032 g H
2 mol C !12.01 g C1 mol C
" 24.02 g C
3 mol F !19.00 g F1 mol F
" 57.00 g O83.98 g AlF3
1 mol Al !26.98 g Al1 mol Al
" 26.98 g Al
Chemical Quantities
49
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50
Chapter 6
6.21 a.
b.
c.
d.
e.
6.22 a.
b.
c.
d.
e.
6.23 a.
b.
c.
d.
e.
6.24 a.
b.
c.
d.
e.
6.25 a.
b.
c. 15.0 g NH3 !1 mol NH3
17.03 g NH3 " 0.881 mol NH3
0.188 g C !1 mol C
12.01 g C " 0.0240 mol C
82.0 g Ag !1 mol Ag
107.9 g Ag " 0.760 mol Ag
2.28 mol SF6 !146.07 g SF6
1 mol SF6 " 333 g SF6
2.28 mol Mg(HCO3)2 !146.35 g Mg(HCO3)2
1 mol Mg(HCO3)2 " 334 g Mg(HCO3)2
2.28 mol C3H6O3 !90.08 g C3H6O3
1 mol C3H6O3 " 205 g C3H6O3
2.28 mol SO3 !80.07 g SO3
1 mol SO3 " 183 g SO3
2.28 mol N2 !28.02 g N2
1 mol N2 " 63.9 g N2
0.150 mol C6H14 !86.17 g C6H14
1 mol C6H14 " 12.9 g C6H14
0.150 mol Ca(NO3)2 !164.10 g Ca(NO3)2
1 mol Ca(NO3)2 " 24.6 g Ca(NO3)2
0.150 mol Na2O !61.98 g Na2O1 mol Na2O
" 9.30 g Na2O
0.150 mol I2 !253.8 g I2
1 mol I2 " 38.1 g I2
0.150 mol Ne !20.18 g Ne1 mol Ne
" 3.03 g Ne
2.08 mol (NH4)2SO4 !132.15 g (NH4)2SO4
1 mol (NH4)2SO4 " 275 g (NH4)2SO4
0.145 mol C2H6O !46.07 g C2H6O1 mol C2H6O
" 6.68 g C2H6O
3.52 mol MgBr2 !184.11 g MgBr2
1 mol MgBr2 " 648 g MgBr2
0.75 mol Cu !63.55 g Cu1 mol Cu
" 48 g Cu
5.12 mol Al !26.98 g Al1 mol Al
" 138 g Al
7.14 ! 102 mol PCl3 !137.32 g PCl3
1 mol PCl3 " 9.80 ! 104 g PCl3
0.0485 mol Na2CO3 !105.99 g Na2CO3
1 mol Na2CO3 " 5.14 g Na2CO3
0.125 mol CO2 !44.01 g CO2
1 mol CO2 " 5.50 g CO2
2.80 mol Ca !40.08 g Ca1 mol Ca
" 112 g Ca
1.50 mol Na !22.99 g Na1 mol Na
" 34.5 g Na
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d.
e.
6.26 a.
b.
c.
d.
e.
6.27 a.
b.
c.
d.
e.
6.28 a.
b.
c.
d.
e.
6.29 a.
b.
c.
d.
e. 7.5 ! 1024 molecules CH4 !1 atom C
1 molecule CH4" 7.5 ! 1024 C atoms
1.84 mol C2H6O !2 mol C
1 mol C2H6O!
6.022 ! 1023 C atoms1 mol C
" 2.22 ! 1024 C atoms
1.13 ! 1025 C atoms
275 g C3H8 !1 mol C3H8
44.09 g C3H8!
3 mol C 1 mol C3H8
!6.022 ! 1023 C atoms
1 mol C"
0.688 mol C !6.022 ! 1023 C atoms
1 mol C" 4.14 ! 1024 C atoms
25.0 g C !1 mol C
12.01 g C!
6.022 ! 1023 C atoms1 mol C
" 1.25 ! 1024 C atoms
4.00 g C6H8O6 !1 mol C6H8O6
176.12 g C6H8O6 " 0.0227 mol C6H8O6
4.00 g Ca3N2 !1 mol Ca3N2
148.28 g Ca3N2 " 0.0270 mol Ca3N2
4.00 g Cr(OH)3 !1 mol Cr(OH)3
103.02 g Cr(OH)3 " 0.0388 mol Cr(OH)3
4.00 g SnO2 !1 mol SnO2
150.7 g SnO2 " 0.0265 mol SnO2
4.00 g He !1 mol He
4.003 g He " 0.999 mol He
25.0 g C4H10 !1 mol C4H10
58.12 g C4H10 " 0.430 mol C4H10
25.0 g Ga2S3 !1 mol Ga2S3
235.65 g Ga2S3 " 0.106 mol Ga2S3
25.0 g Al(OH)3 !1 mol Al(OH)3
78.00 g Al(OH)3 " 0.320 mol Al(OH)3
25.0 g O2 !1 mol O2
32.00 g O2 " 0.781 mol O2
25.0 g He !1 mol He
4.003 g He " 6.25 mol He
252.8 g C6H12O6 !1 mol C6H12O6
180.16 g C6H12O6 " 1.403 mol C6H12O6
308 g BaSO4 !1 mol BaSO4
233.4 g BaSO4 " 1.32 mol BaSO4
6.4 g H2O !1 mol H2O
18.02 g H2O " 0.36 mol H2O
144 g K !1 mol K
39.10 g K " 3.68 mol K
85.2 g Ni !1 mol Ni
58.69 g Ni " 1.45 mol Ni
245 g Fe2O3 !1 mol Fe2O3
159.7 g Fe2O3 " 1.53 mol Fe2O3
7.25 g C3H8 !1 mol C3H8
44.09 g C3H8 " 0.164 mol C3H8
Chemical Quantities
51
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52
Chapter 6
6.30 a.
b.
c.
d.
e.
6.31 a.
b.
c.
d.
6.32 a. 0.203 mol Sb.c. 50.3 g Cd.
6.33 a.
b.
2.016 g H74.10 g Ca(OH)2
! 100% " 2.72% H (rounded to 0.01%)
32.00 g O74.10 g Ca(OH)2
! 100% " 42.18% O
40.08 g Ca74.10 g Ca(OH)2
! 100% " 54.09% Ca
2 mol H !1.008 g H1 mol H
" 2.016 g H
74.10 g Ca(OH)2
2 mol O !16.00 g O1 mol O
" 32.00 g O
1 mol Ca !40.08 g Ca1 mol Ca
" 40.08 g Ca
38.00 g F62.31 g MgF2
! 100% " 60.99% F
24.31 g Mg62.31 g MgF2
! 100% " 39.01% Mg
2 mol F !19.00 g F1 mol F
" 38.00 g F62.31 g MgF2
1 mol Mg !24.31 g Mg1 mol Mg
" 24.31 g Mg
4.75 ! 1023 C atoms
4.5 ! 1024 atoms H
" 2.78 ! 1022 atoms H
0.254 g C3H8 !1 mol C3H8
44.09 g C3H8!
8 mol H1 mol C3H8
!6.022 ! 1023 atoms H
1 mol H
0.771 mol C3H8 !3 mol C
1 mol C3H8!
12.01 g C1 mol C
" 27.8 g C
34.0 g C3H8 !1 mol C3H8
44.09 g C3H8" 0.771 mol propane (C3H8)
1.50 mol C3H8 !44.09 g C3H8
1 mol C3H8" 66.1 g propane (C3H8)
1.4 ! 1022 molecules N2O4 !2 atoms N
1 molecule N2O4" 2.8 ! 1022 N atoms
6.24 ! 10#3 mol NH3 !1 mol N
1 mol NH3!
6.022 ! 1023 N atoms1 mol N
" 3.76 ! 1021 N atoms
40.0 g N2O !1 mol N2O
44.02 g N2O!
2 mol N1 mol N2O
!6.022 ! 1023 N atoms
1 mol N" 1.09 ! 1024 N atoms
5.8 ! 1021 N atoms
0.82 g NaNO3 !1 mol NaNO3
85.00 g NaNO3!
1 mol N1 mol NaNO3
!6.022 ! 1023 N atoms
1 mol N"
0.755 mol N2 !2 mol N1 mol N2
!6.022 ! 1023 N atoms
1 mol N" 9.09 ! 1023 N atoms
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c.
d.
e.
48.00 g O285.3 g C17H19NO3
! 100% " 16.82% O
14.01 g N285.3 g C17H19NO3
! 100% " 4.91% N (rounded to 0.01%)
19.15 g H285.3 g C17H19NO3
! 100% " 6.71% H (rounded to 0.01%)
204.2 g C285.3 g C17H19NO3
! 100% " 71.56% C
3 mol O !16.00 g O1 mol O
" 48.00 g O
285.3 g C17H19NO3
1 mol N !14.01 g N1 mol N
" 14.01 g N
19 mol H !1.008 g H1 mol H
" 19.15 g H
17 mol C !12.01 g C1 mol C
" 204.2 g C
64.00 g O149.10 g C4H8O4
! 100% " 42.92% O
30.97 g P149.10 g C4H8O4
! 100% " 20.77% P
12.10 g N149.10 g C4H8O4
! 100% " 8.12% H (rounded to 0.01%)
43.03 g N149.10 g C4H8O4
! 100% " 28.19% N
4 mol O !16.00 g O1 mol O
" 64.00 g O
149.10 g C4H8O4
1 mol P !30.97 g P1 mol P
" 30.97 g P
12 mol H !1.008 g H1 mol H
" 12.10 g H
3 mol N !14.01 g N1 mol N
" 42.03 g N
64.00 g O120.10 g C4H8O4
! 100% " 53.29% O
8.064 g H120.10 g C4H8O4
! 100% " 6.71% H (rounded to 0.01%)
48.04 g C120.10 g C4H8O4
! 100% " 40.00% C
4 mol O !16.00 g O1 mol O
" 64.00 g O
120.10 g C4H8O4
8 mol H !1.008 g H1 mol H
" 8.06 g H (rounded to 0.01%)
4 mol C !12.01 g C1 mol C
" 48.04 g C
Chemical Quantities
53
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54
Chapter 6
6.34 a. 36.11% Ca; 63.89% Clb. 17.55% Na; 39.70% Cr; 42.75% Oc. 18.01% C; 2.27% H; 79.73% Cld. 38.76% Ca; 19.97% P; 41.27% Oe. 75.99% C; 12.76% H; 11.25% O
6.35 a.
b.
c.
d.
e.
28.02 g N234.3 g C14H22N2O
! 100% " 11.96% N
1 mol O !16.00 g O1 mol O
" 16.00 g O
234.3 g C14H22N2O
2 mol N !14.01 g N1 mol N
" 28.02 g N
22 mol H !1.008 g H1 mol H
" 22.18 g H
14 mol C !12.01 g C1 mol C
" 168.1 g C
70.05 g N209.3 g C9H15N5O
! 100% " 33.48% N
1 mol O !16.00 g O1 mol O
" 16.00 g O
209.3 g C9H15N5O
5 mol N !14.01 g N1 mol N
" 70.05 g N
15 mol H !1.008 g H1 mol H
" 15.12 g H
9 mol C !12.01 g C1 mol C
" 108.0 g C
28.02 g N60.10 g C2H8N2
! 100% " 46.62% N
3 mol N !14.01 g N1 mol N
" 28.02 g N60.10 g C2H8N2
8 mol H !1.008 g H1 mol H
" 8.064 g H
2 mol C !12.01 g C1 mol C
" 24.02 g C
28.02 g N80.05 g NH4NO3
! 100% " 35.00% N
3 mol O !16.00 g O1 mol O
" 48.00 g O80.05 g NH4NO3
4 mol H !1.008 g H1 mol H
" 4.032 g H
2 mol N !14.01 g N1 mol H
" 28.02 g N
28.02 g N108.20 g N2O5
! 100% " 25.94% N
5 mol O !16.00 g O1 mol O
" 80.00 g O
108.20 g N2O5
2 mol N !14.01 g N1 mol N
" 28.02 g N
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 54
6.36 a. 22.58% S b. 64.07% S c. 40.05% Sd. 41.04% S e. 12.81% S
6.37 a.
b.
c.
d.
6.38 a. b. c. d.
6.39 11.44 g compound (S and F)
Empirical formula " SF6
0.0783 mol S0.0783 mol
" 1.00 mol S 0.470 mol F0.0783
" 6.00 mol F
8.93 g F !1 mol F
19.00 g F" 0.470 mol F
2.51 g S !1 mol S
32.07 g S" 0.0783 mol S (smaller number of moles)
# 2.51 g S " 8.93 g F
K3PO4NaHSO4Na2OAg2S
0.205 mol O0.0512
" 4.00 mol O Empirical formula " CaCrO4
0.0514 mol Ca0.0512
" 1.00 mol Ca 0.0512 mol Cr0.0512
" 1.00 mol Cr
3.28 g O !1 mol O
16.00 g O " 0.205 mol O
2.66 g Cr !1 mol Cr
52.00 g Cr " 0.0512 mol Cr (smaller number of moles)
2.06 g Ca !1 mol Ca
1.008 g Ca " 0.0514 mol Ca
0.524 mol O0.174
" 3.01 mol O Empirical formula " HNO3
0.174 mol H0.174
" 1.00 mol H 0.174 mol N0.174
" 1.00 mol N
8.38 g O !1 mol O
16.00 g O " 0.524 mol O
2.44 g N !1 mol N
14.01 g N " 0.174 mol N (smaller number of moles)
0.175 g H !1 mol H
1.008 g H " 0.174 mol H
Empirical formula " CH3
0.583 mol C0.583
" 1.00 mol C 1.74 mol H0.583
" 2.98 mol H : 3
1.75 g H !1 mol H
1.008 g H" 1.74 mol H
7.00 g C !1 mol C
12.01 g C" 0.583 mol C (smaller number of moles)
Empirical formula " N2O
0.255 mol N0.128
" 1.99 mol N : 2 0.128 mol O0.128
" 1.00 mol O
2.04 g O !1 mol O
16.00 g O" 0.128 mol O (smaller number of moles)
3.57 g N !1 mol N
14.01 g N" 0.255 mol N
Chemical Quantities
55
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 55
56
Chapter 6
6.40
6.41 a.
b.
c.
d.
e.
Empirical formula " C5H8O31.00 mol O ! 3 " 3.00 mol O2.66 mol H ! 3 " 7.98 mol H : 8 H1.67 mol C ! 3 " 5.01 mol C : 5 C
2.58 mol O2.58
" 1.00 mol O
6.85 mol H2.58
" 2.66 mol H4.31 mol C
2.58" 1.67 mol C
41.3 g O !1 mol O
16.00 g O" 2.58 mol O (smaller number of moles)
6.90 g H !1 mol H
1.008 g H" 6.85 mol H51.7 g C !
1 mol C12.01 g C
" 4.31 mol C
Empirical formula " Li2CO34.06 mol O
1.36" 2.98 mol : 3 O
1.36 mol C1.36
" 1.00 mol C2.71 mol Li
1.36" 1.99 mol Li : 2 Li
64.9 g O !1 mol O
16.00 g O " 4.06 mol O
16.3 g C !1 mol C
12.01 g C " 1.36 mol C (smaller number of moles)
18.8 g Li !1 mol Li
6.941 g Li " 2.71 mol Li
Empirical formula " B2O3
1.50 mol O ! 2 " 3.00 mol O1.00 mol B ! 2 " 2.00 mol B
2.87 mol B2.87
" 1.00 mol B 4.31 mol O2.87
" 1.50 mol O
69.0 g O !1 mol O
16.00 g O" 4.31 mol O
31.0 g B !1 mol B
10.81 g B" 2.87 mol B (smaller number of moles)
Empirical formula " GaF3
0.789 mol S0.789
" 1.00 mol Ga 2.36 mol F0.789
" 2.99 mol F : 3 F
45.0 g F !1 mol F
19.00 g F " 2.36 mol F
55.0 g Ga !1 mol Ga
69.72 g Ga " 0.789 mol Ga (smaller number of moles)
Empirical formula " K2S
1.81 mol K0.907
" 2.00 mol K 0.907 mol S0.907
" 1.00 mol S
29.1 g S !1 mol S
32.07 g S " 0.907 mol S (smaller number of moles)
70.9 g K !1 mol K
39.01 g K " 1.81 mol K
Fe2O3
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 56
6.42 a. CaS b. c. d. e.
6.43 a. HO and b. and c.d.e.
6.44 a. b. c. d. CCl e.
6.45
6.46
6.47
6.48
6.49 In 100 g of compound, there is 48.64 g C, 8.16 g H, and 43.20 g O.
2 ! (Empirical formula C3H6O2) " Molecular formula C6H12O4
148 g (molar mass)74.08 g (mass of empirical formula)
" 2.00
Mass of C3H6O2 " 3 ! 12.01 $ 6 ! 1.008 $ 2 ! 16.00 " 74.08 gEmpirical formula " C3H6O2
1.00 mol O ! 2 " 2.00 mol O3.00 mol O ! 2 " 6.00 mol H1.50 mol C ! 2 " 3.00 mol C
2.70 mol O2.70
" 1.00 mol O
4.050 mol C2.70
" 1.50 mol C 8.10 mol H
2.70 " 3.00 mol H
Moles of O " 43.20 g O ! 1 mol O
16.00 g O " 2.70 mol O (smaller number of moles)
Moles of H " 8.16 g H ! 1 mol H
1.008 g H " 8.10 mol H
Moles of C " 48.64 g C ! 1 mol C
12.01 g C " 4.050 mol C
CHO ! 6 " C6H6O6Acontic acid 174.1 g (molar mass)
29.02 g (mass of empirical formula)" 6.0
CHO ! 4 " C4H4O4Maleic acid 116.1 g (molar mass)29.02 g (mass of empirical formula)
" 4.0
CHO ! 2 " C2H2O2Glyoxyl 58 g (molar mass)29.02 g (empirical mass)
" 2.0
Mass of empirical formula CHO " 12.01 $ 1.008 $ 16.00 " 29.02g
CH ! 2 " C2H2Acetylene 26 g (molar mass)13.02 g (mass of empirical formula)
" 2.0
CH ! 6 " C6H6Benzene 78 g (molar mass)13.02 g (empirical mass)
" 6.0
Mass of empirical formula CH " 12.01 $ 1.008 " 13.02 g
C8H10N4O2
CH2O ! 6 " C6H12O6180 g (molar mass)
30.03 g (empirical mass)" 6
Mass of CH2O " 12.01 $ 2(1.008) $ 16.00 " 30.03 g
C6H4O3B3H5CH2OC2H2O
2O % 2 " 1O2N % 2 " 1N4H % 2 " 2H2C % 2 " 1CCH2NO6N % 3 " 2N18H % 3 " 6H9C % 3 " 3CC3H6N2
2O % 2 " 1O16H % 2 " 8H10C % 2 " 5CC5H8O12H % 6 " 218C % 6 " 3CC3H2
2O % 2 " 1O2H % 2 " 1H
C3H4Cl4Na2S2O3Zn3P2BaF2
Chemical Quantities
57
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58
Chapter 6
6.50 The empirical formula is , and the molecular formula is .
6.51 In 100 g of compound, there are 54.14 g C, 4.80 g H, and 38.06 g O.
6.52 The empirical formula is , and the molecular formula is .
6.53 In 100 g of compound, there are 74.0 g C and 8.7 g H.
6.54 The empirical formula is CHN, and the molecular formula is .
6.55 a.
b.
2 mol O !16.00 g O1 mol O
" 32.00 g O
2 mol N !14.01 g N1 mol N
" 28.02 g N
8 mol H !1.008 g H1 mol H
" 8.064 g H
10 mol C !12.01 g C1 mol C
" 120.1 g C
C10H8N2O2S2 % 2 " C5H4NOS (empirical formula)
C5H5N5
2 ! (Empirical formula C5H7N) " Molecular formula C10H14N2
162 g (molar mass)81.12 g (mass of empirical formula)
" 2.00
Mass of C5H7N1 " 5 ! 12.01 $ 7 ! 1.008 $ 1 ! 14.01 " 81.12 gEmpirical formula " C5H7N1
1.23 mol N1.23
" 1.00 mol N
6.16 mol C1.23
" 5.01 mol C 8.6 mol H
1.23 " 7.0 mol H
Moles of N " 17.3 g N ! 1 mol N
14.01 g N " 1.23 mol N (smallest number of moles)
Moles of H " 8.7 g H ! 1 mol H
1.008 g H " 8.6 mol H
Moles of C " 74.0 g C ! 1 mol C
12.01 g C " 6.16 mol C
100 g # (74.0 g $ 8.7 g) " 17.3 g N
C3H6O3CH2O
4 ! (Empirical formula C2H2O) " Molecular formula C8H8O4
168.1 g (molar mass)42.08 g (mass of empirical formula)
" 3.99 : 4.00
Mass of C2H2O1 " 2 ! 12.01 $ 2 ! 1.008 $ 1 ! 16.00 " 42.04 gEmpirical formula " C2H2O1
2.379 mol O2.379
" 1.00 mol O
4.758 mol C2.379
" 2.00 mol C 4.76 mol H
2.379 " 2.00 mol H
Moles of O " 38.06 g O ! 1 mol O
16.00 g O " 2.379 mol O (smaller number of moles)
Moles of H " 4.80 g H ! 1 mol H
1.008 g H " 4.76 mol H
Moles of C " 54.14 g C ! 1 mol C
12.01 g C " 4.758 mol C
C2H3Cl3O2C2H3Cl3O2
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 58
c.
d.
6.56 a. 15.51% O b.c. 1.13 g hydrogen d.
6.57 a.b. SClc.d.
6.58 a.b. CHc.d.
6.59 a.
b.
6 O atoms !16.00 amu1 O atom
" 96.00 amu389.9 amu
2 I atoms !126.9 amu1 I atom
" 253.8 amu
1 Ca atom !40.08 amu1 Ca atom
" 40.08 amu
4 O atoms !16.00 amu1 O atom
" 64.00 amu
151.92 amu
1 S atom !32.07 amu1 S atom
" 32.07 amu
1 Fe atom !55.85 amu1 Fe atom
" 55.85 amu
6.048 g H/72.06 g C6H6 ! 100% " 7.946% H6 mol H ! 1.008 g/mol H " 6.048 g H72.06 g C/72.06 g C6H6 ! 100% " 92.25% C6 mol C ! 12.01 g/mol C " 72.06 g C6 mol C ! 12.01 g/mol C # 6 mol H ! 1.008 g/mol H " 78.11 g (molar mass)
C6H6
70.90 g Cl/135.04 g S2Cl2 ! 100% " 52.50% Cl2 mol Cl ! 35.45 g/mol Cl " 70.90 g Cl64.14 g S/135.04 g S2Cl2 ! 100% " 47.50% S2 mol S ! 32.07 g/mol S " 64.14 g S2 mol S ! 32.07 g/mol S # 2 mol Cl ! 35.45 g/mol Cl " 135.04 g (molar mass)
S2Cl2
1.29 ! 1022 hydrogen atoms1.61 ! 1022 carbon atoms
6.8 mol C10H8N2O2S2
8.2 ! 1024 N atoms !1 mol N
6.022 ! 1023 N atoms!
1 mol C10H8N2O2S2
2 mol N"
6.022 ! 1023 C atoms1 mol C
" 5.97 ! 1023 C atoms
25.0 g C10H8N2O2S2 !1 mol C10H8N2O2S2
252.3 g C10H8N2O2S2!
10 mol C1 mol C10H8N2O2S2
!
64.14 g S252.3 g C10H8N2O2S2
! 100 " 25.42% S
32.00 g O252.3 g C10H8N2O2S2
! 100 " 12.68% O
28.04 g N252.3 g C10H8N2O2S2
! 100 " 11.10% N
8.064 g H252.3 g C10H8N2O2S2
! 100 " 3.20% H (rounded to 0.01%)
120.1 g C252.3 g C10H8N2O2S2
! 100 " 47.60% C
2 mol S !32.07 g S1 mol S
"64.14 g S
252.3 g C10H8N2O2S2
Chemical Quantities
59
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60
Chapter 6
c.
d.
6.60 a. 146.35 g/mol b. 248.0 g/mol c. 282.5 g/mol d. 358.4 g/mol
6.61 a.
b.
144.0 g O210.0 g Al(HCO3)3
! 100% " 68.57% O
36.03 g C210.0 g Al(HCO3)3
! 100% " 17.16% C
3.024 g H210.0 g Al(HCO3)3
! 100% " 1.44% H (rounded to 0.01%)
26.98 g Al210.0 g Al(HCO3)3
! 100% " 12.85% Al
9 mol O !16.00 g O1 mol O
" 144.0 g O210.0 g Al(HCO3)3
3 mol C !12.01 g C1 mol C
" 36.03 g C
3 mol H !1.008 g H1 mol H
" 3.024 g H
1 mol Al !26.98 g Al1 mol Al
" 26.98 g Al
64.00 g O194.20 g K2CrO4
! 100% " 32.96% O
52.00 g Cr194.20 g K2CrO4
! 100% " 26.78% Cr
78.20 g K194.20 g K2CrO4
! 100% " 40.27% K
4 mol O !16.00 g O1 mol O
" 64.00 g O
194.20 g K2CrO4
1 mol Cr !52.00 g Cr1 mol Cr
" 52.00 g Cr
2 mol K !39.10 g K1 mol K
" 78.20 g K
2 O atoms !16.00 amu1 O atom
" 32.00 amu
116.16 amu
12 H atoms !1.008 amu1 H atom
" 12.10 amu
6 C atoms !12.01 amu1 C atom
" 72.06 amu
4 O atoms !16.00 amu1 O atom
" 64.00 amu
169.11 amu
1 Na atom !22.99 amu1 Na atom
" 22.99 amu
1 N atom !14.01 amu1 N atom
" 14.01 amu
8 H atoms !1.008 amu1 H atom
" 8.064 amu
5 C atoms !12.01 amu1 C atom
" 60.05 amu
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 60
c.
6.62 a. 43.64% P b. 45.93% P c. 19.97% P
6.63 a.
b.
c.
d.
6.64 a. 21.20% Nb.c. 47.8 g oxygend. 10.3 g ammonium sulfate
6.65 a.
b.
c.
1.00 ! 1023 O atoms
7.50 g C9H8O4 !1 mol C9H8O4
90.08 g C9H8O4!
4 mol O1 mol C9H8O4
!6.022 ! 1023 O atoms
1 mol O"
0.923 mol C9H8O4 (aspirin)
5.00 ! 1024 C atoms !1 mol C
6.022 ! 1023 C atoms!
1 mol C9H8O4
9 mol C"
64.00 g O180.2 g C9H8O4
! 100 " 35.52% O
8.064 g H180.2 g C9H8O4
! 100 " 4.48% H (rounded to 0.01%)
108.1 g C180.2 g C9H8O4
! 100 " 59.99% O
4 mol O !16.00 g O1 mol O
" 64.00 g O
180.2 g C3H6O3
8 mol H !1.008 g H1 mol H
" 8.064 g H
9 mol C !12.01 g C1 mol C
" 108.01 g C
3.6 ! 1024 hydrogen atoms
C3H6O3 % 3 " CH2O (empirical formula)
3.50 g H !1 mol H
1.008 g H!
1 mol C3H6O3
6 mol H!
90.08 g C3H6O3
1 mol C3H6O3" 52.1 g C3H6O3
2.51 ! 1024 C atoms
125 g C3H6O3 !1 mol C3H6O3
90.08 g C3H6O3!
3 mol C1 mol C3H6O3
!6.022 ! 1023 C atoms
1 mol C"
48.00 g O90.08 g C3H6O3
! 100 " 53.29% O
3 mol O !16.00 g O1 mol O
" 48.00 g O90.08 g C3H6O3
6 mol H !1.008 g H1 mol H
" 6.048 g H
3 mol C !12.01 g C1 mol C
" 36.03 g C
96.00 g O180.16 g C6H12O6
! 100% " 53.29% O
96.00 g O180.16 g C6H12O6
! 100% " 6.71% H (rounded to 0.01%)
72.06 g C180.16 g C6H12O6
! 100% " 40.00% C
6 mol O !16.00 g O1 mol O
" 96.00 g
180.16 g
12 mol H !1.008 g H1 mol H
" 12.10 g6 mol C !12.01 g C1 mol C
" 72.06 g
Chemical Quantities
61
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62
Chapter 6
d.
6.66 a.b.c.d.
6.67 a.
b.
6.68 a. 115 g Cl b. 0.914 mol P
6.69 a.b.c.d.
6.70 a. b. c. d.
6.71 a.
b.
Empirical formula " AgNO3
0.177 mol O0.0589
" 3.01 mol O
0.0589 mol Ag0.0589
" 1.00 mol Ag 0.0589 mol N0.0589
" 1.00 mol N
Moles of O " 2.83 g O ! 1 mol O
16.00 g O " 0.177 mol O
Moles of N " 0.825 g N ! 1 mol N
14.01 g N " 0.0589 mol N
Moles of Ag " 6.35 g Ag ! 1 mol Ag
107.9 g Ag " 0.0589 mol Ag (smaller number of moles)
Empirical formula " SF6
0.0686 mol S0.0686
" 1.00 mol S 0.411 mol F0.0686
" 5.99 mol F : 6 mol F
7.81 g F !1 mol F
19.00 g F" 0.411 mol F
2.20 g S !1 mol S
32.07 g S" 0.0686 mol S (smaller number of moles)
C8H8NOCrCl3C2H2ONH2
C6H14N2O2 % 2 " C3H7NO (empirical formula)C16H16N4 % 4 " C4H4N (empirical formula)FeC2O4 % 1 " FeC2O4 (empirical formula)C5H5N5 % 5 " CHN (empirical formula)
12.6 g Mn $ 27.5 g Mn " 40.1 g Mn
0.250 mol Mn2O3 !2 mol Mn
1 mol Mn2O3!
54.94 g Mn1 mol Mn
" 27.5 g Mn
20.0 g MnO2 !1 mol MnO2
86.94 g MnO2!
1 mol Mn1 mol MnO2
!54.94 g Mn1 mol Mn
" 12.6 g Mn
1.210 mol O !6.022 ! 1023 O atoms
1 mol O" 7.287 ! 1023 O atoms, or 7.29 ! 1023 O atoms
0.750 mol O $ 0.460 mol O " 1.210 mol O
20.0 g MnO2 !1 mol MnO2
86.94 g MnO2!
2 mol O1 mol MnO2
" 0.460 mol O
0.250 mol Mn2O3 !3 mol O
1 mol Mn2O3" 0.750 mol O
2.3 ! 1021 hydroxide ions3.4 ! 1021 magnesium atoms6.6 ! 1021 calcium ions0.066 mol CaCO3
1.87 ! 1023 molecules (aspirin)
2.50 g H !1 mol H
1.008 g H!
1 mol C9H8O4
8 mol H!
6.022 ! 1023 molecules C9H8O4
1 mol C9H8O4"
47374_06_p43-66.qxd 2/9/07 8:40 AM Page 62
c.
6.72 a. b. c.
6.73 a. In 100 g of compound, there are 76.54 g C, 12.13 g H, and 11.33 g O.
b.
6.74 a. 9.85 g b. c. 0.0820 mol Fe
6.75 In 100 g of compound, there are 40.7 g C, 5.12 g H, and 54.2 g O.
2 ! (Empirical formula C2H3O2) " Molecular formula C4H6O4
118 g (molar mass)59.04 g (mass of empirical formula)
" 2.00
Empirical formula " C2H3O2 " 2 ! 12.01 $ 3 ! 1.008 $ 2 ! 16.00 " 59.04 g1.00 mol C ! 2 " 2.00 mol C 1.50 mol H ! 2 " 3.00 mol H 1.00 mol O ! 2 " 2.00 mol O
3.39 mol O3.39
" 1.00 mol O
3.39 mol C3.39
" 1.00 mol C 5.08 mol H
3.39 " 1.50 mol H
Moles of O " 54.2 g O ! 1 mol O
16.00 g O " 3.39 mol O (smaller number of moles)
Moles of H " 5.12 g H ! 1 mol H
1.008 g H " 5.08 mol H
Moles of C " 40.7 g C ! 1 mol C
12.01 g C " 3.39 mol C
FeS2
5.73 ! 1021 molecules of oleic acid
3.00 mL !0.895 g C18H34O2
1 mL!
1 mol C18H34O2
282.4 g C18H34O2!
6.022 ! 1023 molecules1 mol C18H34O2
"
2 ! (Empirical formula C9H17O) " Molecular formula C18H34O2
282 g (molar mass)141.2 g (mass of empirical formula)
" 2.00
Empirical formula " C9H17O " 9 ! 12.01 $ 17 ! 1.008 $ 1 ! 16.00 " 141.2 g
0.7081 mol O0.7081
" 1.000 mol O
6.373 mol C0.7081
" 9.000 mol C 12.03 mol H
0.7081 " 16.99 : 17 mol H
Moles of O " 11.33 g O ! 1 mol O
16.00 g O " 0.7081 mol O (smaller number of moles)
Moles of H " 12.13 g H ! 1 mol H
1.008 g H " 12.03 mol H
Moles of C " 76.54 g C ! 1 mol C
12.01 g C " 6.373 mol C
AlPO4N2O5SnF4
Empirical formula " Au2O3
0.681 mol O0.453
" 1.50 mol O ! 2 " 3.00 mol O
0.453 mol Au0.453
" 1.00 mol Au ! 2 " 2.00 mol Au
10.9 g O !1 mol O
16.00 g O" 0.681 mol O
89.2 g Au !1 mol Au
197.0 g Au" 0.453 mol Au (smaller number of moles)
Chemical Quantities
63
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64
Chapter 6
6.76 Empirical formula ; Molecular formula
6.77 Moles of
Moles of
Moles of (smaller number of moles)
Empirical formula ; Molecular formulaMolar mass
6.78 Molecular formula
6.79 a. 0.00680 mol NaFb. ions are in the tube.c.d. triclosan molecules are in the tube.e. 49.78% C; 2.44% H; 36.73% Cl; 11.05% O
6.80 The empirical formula is , and the molecular formula is .
6.81 The empirical formula is , and the molecular formula is .
6.82 a.b. Au atomsc.d.
Answers to Combining Ideas Chapters 4–6
CI 6 a. b. calcium carbonate c. ions
CI 7 a. In 100 g oxalic acid,
Dividing each by 2.16,
Empirical formulab. Empirical formula mass
molecular formula(CHO2) ! 2 " C2H2O4
90. g molar mass/45.02 g EF " 2" 12.01 g C $ 1.008 g H $ 2(16.00 g O) " 45.02 g EF
" CHO2
4.44 mol O/2.16 " 2.06 mol O : 22.22 mol H/2.16 " 1.03 mol H : 12.16 mol C/2.16 " 1 mol C : 1
71.1 g O !1 mol O
16.00 g O" 4.44 mol O
2.24 g H !1 mol H
1.008 g H" 2.22 mol H
26.7 g C !1 mol C
12.01 g C" 2.16 mol C
6.02 ! 1021 Ca2$CaCO3
Au2O3
0.61 g oxygen1.52 ! 10225.00 g gold
Fe2Cr3O12Fe2Cr3O12
C6H8O2C3H4O
7.4 ! 10200.00197 g Na$4.10 ! 1021 F#
" SrO6Cl2
" 4 ! 12.01 $ 8 ! 1.008 $ 4 ! 16.00 " 120.10 g" CH2O ! 4 " C4H8O4" CH2O
0.274 mol O0.274
" 1.00 mol O
0.274 mol C0.274
" 1.00 mol C 0.548 mol H
0.274 " 2.00 mol H
O " 4.39 g O !1 mol O
16.00 g O" 0.274 mol O
H " 0.552 g H !1 mol H
1.008 g H" 0.548 mol H
C " 1.65 ! 1023atoms C !1 mol C
6.022 ! 1023atoms C" 0.274 mol C
" Hg2Cl2O6" HgClO3
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c.
d.
CI 8 a.b.c. 54.53% C, 9.15% H, 36.32% Od. 0.464 g Ce. 24.0 gf. 6.
CI 9 a.
b.
c.
d.
Total number of protons
CI 10 a. mol shikimic acidb. 59 capsulesc. 0.046 g Cd.e. 3 ! 104 lb
4 ! 102 kg
7.5 ! 10#3
" 92 protons
5 O atoms !8 protons1 O atom
" 40 protons
10 H atoms !1 proton1 H atom
" 10 protons
7 C atoms !6 protons1 C atom
" 42 protons
C7H10O5
32.00 g O312.40 g
! 100 " 20.49% O
28.02 g N312.40 g
! 100 " 8.97% N
28.88 g H312.40 g
! 100 " 9.03% H
192.16 g C312.40 g
! 100 " 61.51% C
8(12.01 g C) $ 14(1.008 g H) $ 14.01 g N $ 2(16.00 g O) " 312.40 g (molar mass)C8H14NO2
15 ! 10#3 mol butyric acid
C2H4OC4H8O2
27 g !100 g rhubarb leaves
0.5 g!
1 kg1000 g
" 5 kg rhubarb leaves
160 lb !1 kg
2.205 lb!
375 mg1 kg
!1 g
1000 mg" 27 g oxalic acid
Chemical Quantities
65
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