handout notes
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Chemistry notesTRANSCRIPT
Nam
ing Coordination C
ompounds
(nomenclature)
•T
he cation is written before the anion
•T
he charge of the cation(s) is balanced by thecharge of the anion(s)
•In the com
plex ion, neutral ligands are written
before anionic ligands, and the whole ion is
placed in brackets
Rules for w
riting coordination compounds:
Nam
es of some com
mon ligands
Neutral L
igands:H
2 O
Aqua
NH
3A
mm
ineC
OC
arbonylN
ON
itrosyl
Anionic L
igands:F
-Fluoro
Cl -
Chloro
Br -
Brom
oI -
IodoO
H-
Hydroxo
CN
-C
yano
Latin nam
es used for some m
etal anions:
IronFerrate
Copper
Cuprate
Lead
Plumbate
Tin
StannateG
old A
urateSilver
Argentate
Exam
ple: K2 [C
o(NH
3 )2 Cl4 ]
Cations:2xK
+A
nion:
[Co(N
H3 )2 C
l4 ] 2-
NH
3 is neutralC
l - is negativeT
he metal m
ust be Co
2+
Check:
Charge of com
plex = charge of cations +
charge of anions0
+2
-2
See Summ
ary on page 926R
ules for naming coordination com
pounds
Nam
ing coordination compounds
Exam
ple: What is the nam
e for [Co(N
H3 )5 C
l]Cl2 ?
Charge of m
etal ion = charge of
- total charge of
complex ion
all ligands =
2+
- [(5x0) +
(1-)] =
3+i.e. C
o3+, or C
obalt(III)5 N
H3 ligands
pentaam
mine
1 Cl - ligand
chloro
Com
plex ion = pentaam
minechlorocobalt(III)
Counter ion =
chloride
[Co(N
H3 )5 C
l]Cl2 =
pentaamm
inechlorocobalt(III) chloride
Exam
ple: What is the nam
e for K3 F
e(CN
)6 ?
Charge of m
etal ion = charge of
- total charge of
complex ion
all ligands =
3+
- 6x(1-)
= 3+
i.e. Fe
3+, or Iron(III)6 C
N ligands
hexacyano
Com
plex ion = hexacyanoferrate(III)
Counter ion =
potassium
K3 F
e(CN
)6 = potassium
hexacyanoferrate(III)
Exam
ple: What is the nam
e for [Fe(en)2 (N
O2 )2 ]2 SO
4 ?
Exam
ple: What is the form
ula fortriam
minebrom
oplatinum(II) chloride?
[Pt(N
H3 )3 B
r] + and
Cl -
[Pt(N
H3 )3 B
r]Cl
Exam
ple: What is the form
ula for potassiumhexafluorocolbaltate(III)?
Isomers
2 or more chem
ical species with identical
composition but different properties
Figure 20.9
Exam
ple:[C
r(NH
3 )5 SO4 ]B
rand
[Cr(N
H3 )5 B
r]SO4
Exam
ple:[C
o(NH
3 )4 (NO
2 )Cl]C
l(binds through N
- nitro)
and
Co(N
H3 )4 (O
NO
)Cl]C
l(binds through O
- nitrito)
Figure 20.10
Linkage Isom
ers
Pt
NH
3
NH
3
Cl
Cl
Pt
NH
3
NH
3
Cl
Cl
Geom
etric isomers:
cis-Pt(N
H3 )2 C
l2trans-P
t(NH
3 )2 Cl2
These w
ere the isomers W
erner studied
Figure 20.12
cis- and trans-dichloro Isomers
Stefan Bernhard’s son drew
a picture:
Mirror Plane
mb
md
Non-chiral:
Chiral:
Optical isom
ers:isom
ers that have nonsuperimposable m
irror images
= enantiom
ersd- enantiom
er
Rotates plane polarized
light to the right-dextrorotatory (+
θ)
l- enantiomer
Rotates plane polarized
light to the left-levorotatory (-θ)
Figure 20.14
Rotation of plane polarized light by
chiral compounds
Figure 20.16
Figure 20.17