Download Chapter 19 Worksheet

Chem 1C – Chapter 19 – CLAS
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website: clas.sa.ucsb.edu/staff/terri/
1. Which of the following substances can NOT act as a ligand?
a. H2O
b. OH–
c. CO
d. NH4+
e. Br–
2. Which of the following can act as a chelate? Circle all that apply.
a. NH2CH2CH2NH2
b. C2O42–
c. NH2CH2CH2NHCH2CH2NH2
d. SCN–
3. Write the chemical formula for the following:
a. lithium hexahydroxoferrate(III)
b. diamminedichloro(ethylendiamine)chromium(III) sulfate
c. potassium tetrabromodicyanoplatinate(II)
d. bis(ethylenediamine)oxalatomanganese(IV) nitrate
4. For each of the following 1) what is the oxidation state on the transition metal 2) determine the coordination number
and 3) provide a name:
a. [Pt(NH ) Br]
+
3 3
b. K[Co(en)BrCl ]
3
c. [Ni(CO)4] Br2
d. Na[Mn(C2O4)2(CN)2]
e. [Cu(NH3)4(H2O)2][PtI6]
5. Which of the following can NOT form linkage isomers?
a. SCN–
b. NO2–
c. NO3–
d. all can form linkage isomers
6. Rank the following 0.1M aqueous solutions by their conductivity in water.
I. [Cr(H2O)6]Cl3
II. [Cr(H2O)4Cl2]Cl•(H2O)2
III. [Cr(H2O)5Cl]Cl2•H2O
What type of isomers are illustrated above?
7. Which of the following substances can have geometric isomers?
a. [Co(NH3)5Cl]SO4
b. [Co(NH3)6]Cl3
c. Li[Co(NH3)3Cl3]
d. K[Co(NH3)2Cl4]
e. Na3[CoCl6]
8. Give the number of geometric isomers for the octahedral compound [MA2B2C2], where A, B, and C represent ligands.
a. 1
b. 2
c. 3
d. 5
e. 6
9. For the process Co(NH3)5Cl2+ + Cl–  Co(NH3)4Cl2+ + NH3, what would be the ratio of cis to trans isomers in the
product?
a. 1:1
b. 1:2
c. 1:4
d. 4:1
e. 2:1
10. Which of the following statements about the complex ion Co(en)2Cl2+ is true?
(en = ethylenediamine, NH2CH2CH2NH2)
a. The complex ion contains Co(I).
b. The complex ion exhibits cis and trans geometric isomers, but no optical isomers.
c. The complex ion exhibits two geometric isomers (cis and trans) and two optical isomers.
d. The geometric isomers of the complex ion have identical chemical properties.
11. The compound Co(NH3)4Cl3 (233.44g/mol) has several structural isomers. A solution is made by dissolving 0.875 g
of one of the isomer in 25.0 g of water. The solution freezes at -0.56 °C. (Kf = 1.86 °C kg/mol) Which of the
following is the correct structural isomer?
a. [Co(NH3)4Cl3]
b. [Co(NH3)4Cl2]Cl
c. [Co(NH3)4Cl]Cl2
d. [Co(NH3)4]Cl3
12. Draw the d orbital diagrams according to the crystal field model in order to predict how many unpaired electrons are
in each of the following:
a. [Fe(CN)6]3b. [CoBr6]4c. [Mn(en)2]3+ (tetrahedral)
13. An orange complex and a violet complex were both found to have ferric ion as their central metal; which one absorbs
light with a longer wavelength?
14. Solutions of [Co(NH3)6]3+ , [Co(NO2)6]3-and [CoF6]3- are colored. The solutions were red, yellow and blue. Match the
solution to the color.
15. The complex ion [Zn(H2O)6]2+ is colorless whereas [Ni(H2O)6]2+ is green, explain.
16. A crystal that contains a complex ion is known to absorb 266 kJ/mol. Determine the color of the crystal.
Rules for Naming Coordination Compounds
1. As with any ionic compound, the cation is named before the anion.
2. In naming a complex ion, the ligands are named before the metal ion.
3. The prefixes di, tri etc. are used to denote the number of simple ligands. The
prefixes bis, tris and tetrakis etc. are used for more complicated ligands
(polydentates), or ones with names that contain di, tri and so on.
4. The oxidation state of the central metal ion is designated with a Roman numeral
in parentheses.
5. When more than one type of ligand is present, ligands are named in alphabetical
order. Prefixes are not alphabetized.
6. Complex anions have the suffix ate added to the metal ion.
Negative Ligands
Name
Neutral Ligands
Name
Metal
Anion Complex Name
F-
fluoro
H2O
aqua
iron
ferrate
-
chloro
NH3
ammine
copper
cuprate
-
bromo
CO
carbonyl
lead
plumbate
I-
iodo
NO
nitrosyl
silver
argentate
OH-
hydroxo
NH2CH2CH2NH2 aka en
ethylenediamine
gold
aurate
tin
stannate
Cl
Br
CN
-
cyano
-
nitro
NO2
ONO-
nitrito
C2O42- aka ox
oxalato
SCN-
thiocyanato
Examples of Polydentate Ligands
Isomers
(Same formula but different properties)
Structural Isomers
Stereoisomers
(Different bonds)
(Same bonds, different spatial
arrangements)
Coordination
isomerism –
Linkage
isomerism – same
different ligands
or different ratio
of ligands
ligand bonded
with a different
element
[Cr(H2O)5Br]Cl vs.
[Cr(H2O)5Cl]Br
Or
[Zn(NH3)4][CuCl4] vs.
[Cu(NH3)4][ZnCl4]
Geometric
(cis/trans)
isomerism –
different relative
angles
Optical
Isomerism –
chiral –
asymmetric – non
identical mirror
image
Crystal Field Model
Spectrochemical series:
CN- > NO2- > en > NH3 > H2O > OH- >F- > Cl- > Br- > I-
Complimentary colors:
Red/Green
Orange/Blue
Yellow/Violet
Octahedral
Tetrahedral
Square Planar
Linear
List of Terms