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Chemistry

Steven S. Zumdahl, Susan A. Zumdahl

Chapter 21

Transition Metals and Coordination Chemistry - all with Video Answers

Educators

Chapter Questions

03:12

Problem 1

You isolate a compound with the formula $\mathrm{PtCl}_{4} \cdot 2 \mathrm{KCl}$. From electrical conductance tests of an aqueous solution of the compound, you find that three ions per formula unit are present, and you also notice that addition of $\mathrm{AgNO}_{3}$ does not cause a precipitate. Give the formula for this compound that shows the complex ion present. Explain your findings. Name this compound.

Kevin Chimex
Kevin Chimex
Numerade Educator
03:49

Problem 2

Both $\mathrm{Ni}\left(\mathrm{NH}_{3}\right)_{4}^{2+}$ and $\mathrm{Ni}(\mathrm{SCN})_{4}^{2-}$ have four ligands. The first is paramagnetic, and the second is diamagnetic. Are the complex ions tetrahedral or square planar? Explain.

DC
Devon Chapple
Numerade Educator
02:02

Problem 3

. Which is more likely to be paramagnetic, $\mathrm{Fe}(\mathrm{CN})_{6}^{4-}$ or $\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{2+}$ ? Explain.

Kevin Chimex
Kevin Chimex
Numerade Educator
01:59

Problem 4

A metal ion in a high-spin octahedral complex has two more unpaired electrons than the same ion does in a low-spin octahedral complex. Name some possible metal ions for which this would be true.

DC
Devon Chapple
Numerade Educator
01:26

Problem 5

Oxalic acid is often used to remove rust stains. What properties of oxalic acid allow it to do this?

Arpit Gupta
Arpit Gupta
Numerade Educator
03:13

Problem 6

Four different octahedral chromium coordination compounds exist that all have the same oxidation state for chromium and have $\mathrm{H}_{2} \mathrm{O}$ and $\mathrm{Cl}^{-}$ as the ligands and counterions. When $1 \mathrm{~mol}$ of each of the four compounds is dissolved in water, how many mol of silver chloride will precipitate upon addition of excess $\mathrm{AgNO}_{3} ?$

Susan Hallstrom
Susan Hallstrom
Numerade Educator
02:08

Problem 7

Figure $21.17$ shows that the cis isomer of $\mathrm{Co}(\mathrm{en})_{2} \mathrm{Cl}_{2}^{+}$ is optically active while the trans isomer is not optically active. Is the same true for $\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}^{+} ?$ Explain.

Kevin Chimex
Kevin Chimex
Numerade Educator
03:34

Problem 8

A certain first-row transition metal ion forms many different colored solutions. When four coordination compounds of this metal, each having the same coordination number, are dissolved in wa ter, the colors of the solutions are red, yellow, green, and blue Further experiments reveal that two of the complex ions are para magnetic with four unpaired electrons and the other two are dia magnetic. What can be deduced from this information about th four coordination compounds?

David Collins
David Collins
Numerade Educator
03:09

Problem 9

$\mathrm{CoCl}_{4}^{2-}$ forms a tetrahedral complex ion and $\mathrm{Co}(\mathrm{CN})_{6}{ }^{3-}$ form an octahedral complex ion. What is wrong about the followin; statements concerning each complex ion and the $d$ orbital split ting diagrams?
a. $\mathrm{CoCl}_{4}^{2-}$ is an example of a strong-field case having two un paired electrons.
b. Because $\mathrm{CN}^{-}$ is a weak-field ligand, $\mathrm{Co}(\mathrm{CN})_{6}{ }^{3-}$ will be a low spin case having four unpaired electrons.

Kevin Chimex
Kevin Chimex
Numerade Educator
09:09

Problem 10

The following statements discuss some coordination compounds. For each coordination compound, give the complex ion and the counterions, the electron configuration of the transition metal, and the geometry of the complex ion.
a. $\mathrm{CoCl}_{2} \cdot 6 \mathrm{H}_{2} \mathrm{O}$ is a compound used in novelty devices that predict rain.
b. During the developing process of black-and-white film, silver bromide is removed from photographic film by the fixer. The major component of the fixer is sodium thiosulfate. The equation for the reaction is:
$\operatorname{AgBr}(s)+2 \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}(a q) \longrightarrow \mathrm{Na}_{3}\left[\mathrm{Ag}\left(\mathrm{S}_{2} \mathrm{O}_{3}\right)_{2}\right](a q)+\mathrm{NaBr}(a q)$
c. In the production of printed circuit boards for the electronics industry, a thin layer of copper is laminated onto an insulating plastic board. Next, a circuit pattern made of a chemically resistant polymer is printed on the board. The unwanted copper is removed by chemical etching, and the protective polymer is finally removed by solvents. One etching reaction is:
$\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}(a q)+4 \mathrm{NH}_{3}(a q)+\mathrm{Cu}(s) \longrightarrow 2 \mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}(a q)$
Assume these copper complex ions have tetrahedral geometry.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
04:01

Problem 11

When concentrated hydrochloric acid is added to a red solution containing the $\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{2+}$ complex ion, the solution turns blue as the tetrahedral $\mathrm{CoCl}_{4}{ }^{2-}$ complex ion forms. Explain this color change.

Arpit Gupta
Arpit Gupta
Numerade Educator
01:08

Problem 12

Tetrahedral complexes of $\mathrm{Co}^{2+}$ are quite common. Use $d$ -orbital splitting diagram to rationalize the stability of $\mathrm{Co}^{2+}$ tetrahedral complex ions.

Arpit Gupta
Arpit Gupta
Numerade Educator
02:38

Problem 13

Which of the following ligands are capable of linkage isomerism? Explain your answer.
$$\mathrm{SCN}^{-}, \mathrm{N}_{3}^{-}, \mathrm{NO}_{2}^{-}, \mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}, \mathrm{OCN}^{-}, \mathrm{I}^{-}$$

Kevin Chimex
Kevin Chimex
Numerade Educator
06:29

Problem 14

Compounds of copper(II) are generally colored, but compounds of copper(I) are not. Explain. Would you expect $\mathrm{Cd}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}$ to be colored? Explain.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
01:57

Problem 15

Compounds of $\mathrm{Sc}^{3+}$ are not colored, but those of $\mathrm{Ti}^{3+}$ and $\mathrm{V}^{3+}$ are. Why?

Kevin Chimex
Kevin Chimex
Numerade Educator
01:00

Problem 16

Almost all metals in nature are found as ionic compounds in ores instead of being in the pure state. Why? What must be done to a sample of ore to obtain a metal substance that has desirable properties?

Arpit Gupta
Arpit Gupta
Numerade Educator
02:49

Problem 17

Write electron configurations for the following metals.
a. $\mathrm{Ni}$
b. $\mathrm{Cd}$
c. $\mathrm{Zr}$
d. $\mathrm{Os}$

Kaitlyn Mchugh
Kaitlyn Mchugh
Numerade Educator
09:56

Problem 18

Write electron configurations for the following ions.
a. $\mathrm{Ni}^{2+}$
c. $\mathrm{Zr}^{3+}$ and $\mathrm{Zr}^{4+}$
b. $\mathrm{Cd}^{2+}$
d. $\mathrm{Os}^{2+}$ and $\mathrm{Os}^{3+}$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
04:18

Problem 19

Write electron configurations for each of the following.
a. $\mathrm{Ti}, \mathrm{Ti}^{2+}, \mathrm{Ti}^{\mathrm{i}+}$
b. $\operatorname{Re}, \mathrm{Re}^{2+}, \mathrm{Re}^{3+}$
c. $\mathrm{Ir}, \mathrm{Ir}^{2+}, \mathrm{Ir}^{3+}$

Cameron Oden
Cameron Oden
Numerade Educator
02:19

Problem 20

Write electron configurations for each of the following.
a. $\mathrm{Cr}, \mathrm{Cr}^{2+}, \mathrm{Cr}^{3+}$
b. $\mathrm{Cu}, \mathrm{Cu}^{+}, \mathrm{Cu}^{2+}$
c. $\mathrm{V}, \mathrm{V}^{2+}, \mathrm{V}^{3+}$

Arpit Gupta
Arpit Gupta
Numerade Educator
03:57

Problem 21

What is the electron configuration for the transition metal ion in each of the following compounds?
a. $\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$
b. $\left[\mathrm{Ag}\left(\mathrm{NH}_{3}\right)_{2}\right] \mathrm{Cl}$
c. $\left[\mathrm{Ni}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right] \mathrm{Br}_{2}$
d. $\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{4}\left(\mathrm{NO}_{2}\right)_{2}\right] \mathrm{I}$

Arpit Gupta
Arpit Gupta
Numerade Educator
07:31

Problem 22

What is the electron configuration for the transition metal ion(s) in each of the following compounds?
a. $\left(\mathrm{NH}_{4}\right)_{2}\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2} \mathrm{Cl}_{4}\right]$
b. $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{2}\left(\mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}\right)_{2}\right] \mathrm{I}_{2}$
c. $\mathrm{Na}_{2}\left[\mathrm{TaF}_{7}\right]$
d. $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{I}_{2}\right]\left[\mathrm{Pt} \mathrm{I}_{4}\right]$
Pt forms $+2$ and $+4$ oxidation states in compounds.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
01:39

Problem 23

Molybdenum is obtained as a by-product of copper mining or is mined directly (primary deposits are in the Rocky Mountains in Colorado). In both cases it is obtained as $\mathrm{MoS}_{2}$, which is then converted to $\mathrm{MoO}_{3}$. The $\mathrm{MoO}_{3}$ can be used directly in the production of stainless steel for high-speed tools (which accounts for about $85 \%$ of the molybdenum used). Molybdenum can be purified by dissolving $\mathrm{MoO}_{3}$ in aqueous ammonia and crystallizing ammonium molybdate. Depending on conditions, either $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Mo}_{2} \mathrm{O}_{7}$ or $\left(\mathrm{NH}_{4}\right)_{6} \mathrm{Mo}_{7} \mathrm{O}_{24} \cdot 4 \mathrm{H}_{2} \mathrm{O}$ is obtained.
a. Give names for $\mathrm{MoS}_{2}$ and $\mathrm{MoO}_{3}$.
b. What is the oxidation state of Mo in each of the compounds mentioned above?

Arpit Gupta
Arpit Gupta
Numerade Educator
09:55

Problem 24

Titanium dioxide, the most widely used white pigment, occurs naturally but is often colored by the presence of impurities. The chloride process is often used in purifying rutile, a mineral form of titanium dioxide.
a. Show that the unit cell for rutile, shown below, conforms to the formula $\mathrm{TiO}_{2}$. (Hint: Recall the discussion in Sections $10.4$ and $10.7 .$ )
b. The reactions for the chloride process are
$$\begin{array}{l}2 \mathrm{TiO}_{2}(s)+3 \mathrm{C}(s)+4 \mathrm{Cl}_{2}(g) \\\quad \stackrel{950^{\circ} \mathrm{C}}{\longrightarrow} 2 \mathrm{TiCl}_{4}(g)+\mathrm{CO}_{2}(g)+2 \mathrm{CO}(g) \\
\mathrm{TiCl}_{4}(g)+\mathrm{O}_{2}(g) \stackrel{1000-1400^{\circ} \mathrm{C}}{\longrightarrow} \mathrm{TiO}_{2}(s)+2 \mathrm{Cl}_{2}(g)
\end{array}$$
Assign oxidation states to the elements in both reactions. Which elements are being reduced, and which are being oxidized? Identify the oxidizing agent and the reducing agent in each reaction.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
02:09

Problem 25

What is the lanthanide contraction? How does the lanthanide contraction affect the properties of the $4 d$ and $5 d$ transition metals?

Arpit Gupta
Arpit Gupta
Numerade Educator
01:38

Problem 26

We expect the atomic radius to increase down a group in the periodic table. Can you suggest why the atomic radius of hafnium breaks this rule? (See the following data.)

Cameron Oden
Cameron Oden
Numerade Educator
01:35

Problem 27

Novelty devices for predicting rain contain cobalt(II) chloride and are based on the following equilibrium:
$$\mathrm{CoCl}_{2}(s)+6 \mathrm{H}_{2} \mathrm{O}(g) \rightleftharpoons \mathrm{CoCl}_{2} \cdot 6 \mathrm{H}_{2} \mathrm{O}(s)$$
What color will such an indicator be if rain is imminent?

Ronald Prasad
Ronald Prasad
Numerade Educator
01:05

Problem 28

Chromium(VI) forms two different oxyanions, the orange dichromate ion, $\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}$, and the yellow chromate ion, $\mathrm{CrO}_{4}^{2-} .$ The equilibrium reaction between the two ions is
$$\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}(a q)+\mathrm{H}_{2} \mathrm{O}(l) \rightleftharpoons 2 \mathrm{CrO}_{4}^{2-}(a q)+2 \mathrm{H}^{+}(a q)$$
The following pictures show what happens when sodium hydroxide is added to a dichromate solution.

Anand Jangid
Anand Jangid
Numerade Educator
02:02

Problem 29

A series of chemicals was added to some $\mathrm{AgNO}_{3}(a q) . \mathrm{NaCl}(a q)$ was added first to the silver nitrate solution with the end result shown in test tube $1, \mathrm{NH}_{3}(a q)$ was then added with the end result shown in test tube 2, and $\mathrm{HNO}_{3}(a q)$ was added last with the end result shown in test tube 3 . Explain the results shown in each test tube. Include a balanced equation for the reaction(s) taking place.

Aadit Sharma
Aadit Sharma
Numerade Educator
04:30

Problem 30

When an aqueous solution of $\mathrm{KCN}$ is added to a solution containing $\mathrm{Ni}^{2+}$ ions, a precipitate forms, which redissolves on addition of more KCN solution. Write reactions describing what happens in this solution. [Hint: $\mathrm{CN}^{-}$ is a Brónsted-Lowry base $\left(K_{\mathrm{b}}=10^{-5}\right)$ and a Lewis base. $]$

Arpit Gupta
Arpit Gupta
Numerade Educator
02:18

Problem 31

Consider aqueous solutions of the following coordination compounds: $\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6} \mathrm{I}_{3}, \mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{I}_{4}, \mathrm{Na}_{2} \mathrm{Pt}_{6}$, and $\mathrm{Cr}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{I}_{3} .$ If
aqueous $\mathrm{AgNO}_{3}$ is added to separate beakers containing solutions of each coordination compound, how many moles of AgI will precipitate per mole of transition metal present? Assume that each transition metal ion forms an octahedral complex.

Kevin Chimex
Kevin Chimex
Numerade Educator
05:04

Problem 32

A coordination compound of cobalt(III) contains four ammonia molecules, one sulfate ion, and one chloride ion. Addition of aqueous $\mathrm{BaCl}_{2}$ solution to an aqueous solution of the compound gives no precipitate. Addition of aqueous $\mathrm{AgNO}_{3}$ to an aqueous solution of the compound produces a white precipitate. Propose a structure for this coordination compound.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
05:46

Problem 33

Name the following complex ions.
a. $\mathrm{Ru}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{2+}$
c. $\mathrm{Mn}\left(\mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}\right)_{3}^{2+}$
b. $\mathrm{Fe}(\mathrm{CN})_{6}^{4-}$
d. $\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{NO}_{2}^{2+}$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
06:00

Problem 34

Name the following complex ions.
a. $\mathrm{Ni}(\mathrm{CN})_{4}^{2-}$
c. $\mathrm{Fe}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{5}{ }^{3-}$
b. $\mathrm{Cr}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}^{+}$
d. $\mathrm{Co}(\mathrm{SCN})_{2}\left(\mathrm{H}_{2} \mathrm{O}\right)_{4}^{+}$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
10:54

Problem 35

Name the following coordination compounds.
a. $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right] \mathrm{Cl}_{2}$
d. $\mathrm{K}_{4}\left[\mathrm{PtCl}_{6}\right]$
b. $\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right] \mathrm{I}_{3}$
e. $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}\right] \mathrm{Cl}_{2}$
c. $\mathrm{K}_{2}\left[\mathrm{PtCl}_{4}\right]$
f. $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{3}\left(\mathrm{NO}_{2}\right)_{3}\right]$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
10:15

Problem 36

Name the following coordination compounds.
a. $\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{5} \mathrm{Br}\right] \mathrm{Br}_{2}$
c. $\left[\mathrm{Fe}\left(\mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{NH}_{2}\right)_{2}\left(\mathrm{NO}_{2}\right)_{2}\right] \mathrm{Cl}$
b. $\mathrm{Na}_{3}\left[\mathrm{Co}(\mathrm{CN})_{6}\right]$
d. $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{I}_{2}\right]\left[\mathrm{PtI}_{4}\right]$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
07:21

Problem 37

Give formulas for the following.
a. potassium tetrachlorocobaltate(II)
b. aquatricarbonylplatinum(II) bromide
c. sodium dicyanobis(oxalato)ferrate(III)
d. triamminechloroethylenediaminechromium(III) iodide

Arpit Gupta
Arpit Gupta
Numerade Educator
04:00

Problem 38

Give formulas for the following complex ions.
a. tetrachloroferrate(III) ion
b. pentaammineaquaruthenium(III) ion
c. tetracarbonyldihydroxochromium(III) ion
d. amminetrichloroplatinate(II) ion

Arpit Gupta
Arpit Gupta
Numerade Educator
07:05

Problem 39

Draw geometrical isomers of each of the following complex ions.
a. $\left[\mathrm{Co}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{2}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}\right]^{-}$
c. $\left[\operatorname{Ir}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]$
b. $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{I}_{2}\right]^{2+}$
d. $\left[\mathrm{Cr}(\mathrm{en})\left(\mathrm{NH}_{3}\right)_{2} \mathrm{I}_{2}\right]^{+}$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
09:15

Problem 40

Draw structures of each of the following.
a. cis-dichloroethylenediamineplatinum(II)
b. trans-dichlorobis(ethylenediamine) cobalt(II)
c. cis-tetraamminechloronitrocobalt(III) ion
d. trans-tetraamminechloronitritocobalt(III) ion
e. trans-diaquabis(ethylenediamine) copper(II) ion

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
02:04

Problem 41

The carbonate ion $\left(\mathrm{CO}_{3}^{2-}\right)$ can act as either a monodentate or a bidentate ligand. Draw a picture of $\mathrm{CO}_{3}^{2-}$ coordinating to a metal ion as a monodentate and as a bidentate ligand. The carbonate ion can also act as a bridge between two metal ions. Draw a picture of a $\mathrm{CO}_{3}^{2-}$ ion bridging between two metal ions.

Kevin Chimex
Kevin Chimex
Numerade Educator
04:55

Problem 42

BAL is a chelating agent used in treating heavy metal poisoning. It acts as a bidentate ligand. What type of linkage isomers are possible when BAL coordinates to a metal ion?

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
03:29

Problem 43

Draw all geometrical and linkage isomers of $\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{4}\left(\mathrm{NO}_{2}\right)_{2}$.

Arpit Gupta
Arpit Gupta
Numerade Educator
10:59

Problem 44

Draw all geometrical and linkage isomers of square planar $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{2}(\mathrm{SCN})_{2}\right]$.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
02:33

Problem 45

Acetylacetone, abbreviated acacH, is a bidentate ligand. It loses a proton and coordinates as acac $^{-}$, as shown below, where $\mathrm{M}$ is a transition metal: Which of the following complexes are optically active: cis$\mathrm{Cr}(\mathrm{acac})_{2}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}$, trans $-\mathrm{Cr}(\mathrm{acac})_{2}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}$, and $\mathrm{Cr}(\mathrm{acac})_{3} ?$

Susan Hallstrom
Susan Hallstrom
Numerade Educator
14:23

Problem 46

Draw all geometrical isomers of $\mathrm{Pt}(\mathrm{CN})_{2} \mathrm{Br}_{2}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}$. Which of these isomers has an optical isomer? Draw the various optical isomers.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
05:17

Problem 47

Draw the $d$ -orbital splitting diagrams for the octahedral complex ions of each of the following.
a. $\mathrm{Fe}^{2+}$ (high and low spin)
b. $\mathrm{Fe}^{3+}$ (high spin)
c. $\mathrm{Ni}^{2+}$

Arpit Gupta
Arpit Gupta
Numerade Educator
07:23

Problem 48

Draw the $d$ -orbital splitting diagrams for the octahedral complex ions of each of the following.
a. $\mathrm{Zn}^{2+}$
b. $\mathrm{Co}^{2+}$ (high and low spin)
c. $\mathrm{Ti}^{3+}$

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
02:35

Problem 49

The $\mathrm{CrF}_{6}^{4-}$ ion is known to have four unpaired electrons. Does the $\mathrm{F}^{-}$ ligand produce a strong or weak field?

Arpit Gupta
Arpit Gupta
Numerade Educator
01:24

Problem 50

The $\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}^{3+}$ ion is diamagnetic, but $\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{2+}$ is paramagnetic. Explain.

Cameron Oden
Cameron Oden
Numerade Educator
03:03

Problem 51

How many unpaired electrons are in the following complex ions?
a. $\mathrm{Ru}\left(\mathrm{NH}_{3}\right)_{6}^{2+}$ (low-spin case)
b. $\mathrm{Ni}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{2+}$
c. $\mathrm{V}(\mathrm{en})_{3}{ }^{3+}$

Kevin Chimex
Kevin Chimex
Numerade Educator
07:41

Problem 52

The complex ion $\mathrm{Fe}(\mathrm{CN})_{6}{ }^{3-}$ is paramagnetic with one unpaired electron. The complex ion $\mathrm{Fe}(\mathrm{SCN})_{6}{ }^{3-}$ has five unpaired electrons. Where does $\mathrm{SCN}^{-}$ lie in the spectrochemical series relative to $\mathrm{CN}^{-}$ ?

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
05:11

Problem 53

Rank the following complex ions in order of increasing wavelength of light absorbed.
$$\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{3+}, \mathrm{Co}(\mathrm{CN})_{6}{ }^{3-}, \mathrm{Col}_{6}{ }^{3-}, \mathrm{Co}(\mathrm{en})_{3}{ }^{3+}$$

Shalini Tyagi
Shalini Tyagi
Numerade Educator
04:57

Problem 54

The complex ion $\left[\mathrm{Cu}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$ has an absorption maximum at around $800 \mathrm{~nm}$. When four ammonias replace water, $\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}\right]^{2+}$, the absorption maximum shifts to around
$600 \mathrm{~nm} .$ What do these results signify in terms of the relative field splittings of $\mathrm{NH}_{3}$ and $\mathrm{H}_{2} \mathrm{O}$ ? Explain.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
03:07

Problem 55

The following test tubes each contain a different chromium complex ion. For each complex ion, predict the predominant color of light absorbed. If the complex ions are $\mathrm{Cr}\left(\mathrm{NH}_{3}\right)_{6}^{3+}, \mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{3+}$, and
$\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{4} \mathrm{Cl}_{2}^{+}$, what is the identity of the complex ion in each test tube? (Hint: Reference the spectrochemical series.)

Kevin Chimex
Kevin Chimex
Numerade Educator
02:05

Problem 56

Consider the complex ions $\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}^{3+}, \mathrm{Co}(\mathrm{CN})_{6}^{3-}$, and $\mathrm{CoF}_{6}^{3-}$.
The wavelengths of absorbed electromagnetic radiation for these compounds (in no specific order) are $770 \mathrm{~nm}, 440 \mathrm{~nm}$, and $290 \mathrm{~nm}$. Match the complex ion to the wavelength of absorbed electromagnetic radiation.

Cameron Oden
Cameron Oden
Numerade Educator
03:16

Problem 57

The wavelength of absorbed electromagnetic radiation for $\mathrm{CoBr}_{4}^{2-}$ is $3.4 \times 10^{-6} \mathrm{~m}$. Will the complex ion $\mathrm{CoBr}_{6}^{4-}$ absorb electromagnetic radiation having a wavelength longer or shorter than $3.4 \times 10^{-6} \mathrm{~m}$ ? Explain.

Kevin Chimex
Kevin Chimex
Numerade Educator
09:41

Problem 58

The complex ion $\mathrm{NiCl}_{4}^{2-}$ has two unpaired electrons, whereas $\mathrm{Ni}(\mathrm{CN})_{4}^{2-}$ is diamagnetic. Propose structures for these two complex ions.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
01:55

Problem 59

How many unpaired electrons are present in the tetrahedral ion $\mathrm{FeCl}_{4}^{-} ?$

Arpit Gupta
Arpit Gupta
Numerade Educator
01:31

Problem 60

The complex ion $\mathrm{PdCl}_{4}{ }^{2-}$ is diamagnetic. Propose a structure for $\mathrm{PdCl}_{4}^{2-}$

Arpit Gupta
Arpit Gupta
Numerade Educator
04:12

Problem 61

A blast furnace is used to reduce iron oxides to elemental iron. The reducing agent for this reduction process is carbon monoxide.
a. Given the following data:
$\mathrm{Fe}_{2} \mathrm{O}_{3}(s)+3 \mathrm{CO}(g) \longrightarrow 2 \mathrm{Fe}(s)+3 \mathrm{CO}_{2}(g) \quad \Delta H^{\circ}=-23 \mathrm{~kJ}$
$3 \mathrm{Fe}_{2} \mathrm{O}_{3}(s)+\mathrm{CO}(g) \longrightarrow 2 \mathrm{Fe}_{3} \mathrm{O}_{4}(s)+\mathrm{CO}_{2}(g) \quad \Delta H^{\circ}=-39 \mathrm{~kJ}$
$\mathrm{Fe}_{3} \mathrm{O}_{4}(s)+\mathrm{CO}(g) \longrightarrow 3 \mathrm{FeO}(s)+\mathrm{CO}_{2}(g) \quad \Delta H^{\circ}=18 \mathrm{~kJ}$
determine $\Delta H^{\circ}$ for the reaction
$$\mathrm{FeO}(s)+\mathrm{CO}(g) \longrightarrow \mathrm{Fe}(s)+\mathrm{CO}_{2}(g)$$
b. The $\mathrm{CO}_{2}$ produced in a blast furnace during the reduction process actually can oxidize iron into $\mathrm{FeO}$. To eliminate this reaction, excess coke is added to convert $\mathrm{CO}_{2}$ into $\mathrm{CO}$ by the reaction
$$\mathrm{CO}_{2}(g)+\mathrm{C}(s) \longrightarrow 2 \mathrm{CO}(g)$$
Using data from Appendix 4, determine $\Delta H^{\circ}$ and $\Delta S^{\circ}$ for this reaction. Assuming $\Delta H^{\circ}$ and $\Delta S^{\circ}$ do not depend on temperature, at what temperature is the conversion reaction of $\mathrm{CO}_{2}$ into CO spontaneous at standard conditions?

Arpit Gupta
Arpit Gupta
Numerade Educator
01:13

Problem 62

Use the data in Appendix 4 for the following.
a. Calculate $\Delta H^{\circ}$ and $\Delta S^{\circ}$ for the reaction
$$3 \mathrm{Fe}_{2} \mathrm{O}_{3}(s)+\mathrm{CO}(g) \longrightarrow 2 \mathrm{Fe}_{3} \mathrm{O}_{4}(s)+\mathrm{CO}_{2}(g)$$
that occurs in a blast furnace.
b. Assume that $\Delta H^{\circ}$ and $\Delta S^{\circ}$ are independent of temperature. Calculate $\Delta G^{\circ}$ at $800 .{ }^{\circ} \mathrm{C}$ for this reaction.

Arpit Gupta
Arpit Gupta
Numerade Educator
02:30

Problem 63

Iron is present in the earth's crust in many types of minerals. The iron oxide minerals are hematite $\left(\mathrm{Fe}_{2} \mathrm{O}_{3}\right)$ and magnetite $\left(\mathrm{Fe}_{3} \mathrm{O}_{4}\right)$. What is the oxidation state of iron in each mineral? The iron ions in magnetite are a mixture of $\mathrm{Fe}^{2+}$ and $\mathrm{Fe}^{3+}$ ions. What is the ratio of $\mathrm{Fe}^{3+}$ to $\mathrm{Fe}^{2+}$ ions in magnetite? The formula for magnetite is often written as $\mathrm{FeO} \cdot \mathrm{Fe}_{2} \mathrm{O}_{3} .$ Does this make sense? Explain.

Arpit Gupta
Arpit Gupta
Numerade Educator
01:05

Problem 64

What roles do kinetics and thermodynamics play in the effect that the following reaction has on the properties of steel?
$$3 \mathrm{Fe}+\mathrm{C} \rightleftharpoons \mathrm{Fe}_{3} \mathrm{C}$$

Arpit Gupta
Arpit Gupta
Numerade Educator
01:06

Problem 65

Silver is sometimes found in nature as large nuggets; more often it is found mixed with other metals and their ores. Cyanide ion is often used to extract the silver by the following reaction that occurs in basic solution:
$$\mathrm{Ag}(s)+\mathrm{CN}^{-}(a q)+\mathrm{O}_{2}(g) \stackrel{\text { Basis }}{\longrightarrow} \mathrm{Ag}(\mathrm{CN})_{2}^{-}(a q)$$
Balance this equation by using the half-reaction method.

Anand Jangid
Anand Jangid
Numerade Educator
21:06

Problem 66

One of the classic methods for the determination of the manganese content in steel involves converting all the manganese to the deeply colored permanganate ion and then measuring the absorption of light. The steel is first dissolved in nitric acid, producing the manganese(II) ion and nitrogen dioxide gas. This solution is then reacted with an acidic solution containing periodate ion; the products are the permanganate and iodate ions. Write balanced chemical equations for both of these steps.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
03:52

Problem 67

The compound cisplatin, $\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}_{2}$, has been studied extensively as an antitumor agent. The reaction for the synthesis of cisplatin is:
$$\mathrm{K}_{2} \mathrm{PtCl}_{4}(a q)+2 \mathrm{NH}_{3}(a q) \longrightarrow \mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}_{2}(s)+2 \mathrm{KCl}(a q)$$
Write the electron configuration for platinum ion in cisplatin. Most $d^{8}$ transition metal ions exhibit square planar geometry. With this and the name in mind, draw the structure of cisplatin.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
06:10

Problem 68

Amino acids can act as ligands toward transition metal ions. The simplest amino acid is glycine $\left(\mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CO}_{2} \mathrm{H}\right)$. Draw a structure of the glycinate anion $\left(\mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CO}_{2}^{-}\right)$ acting as a bidentate ligand. Draw the structural isomers of the square planar complex $\mathrm{Cu}\left(\mathrm{NH}_{2} \mathrm{CH}_{2} \mathrm{CO}_{2}\right)_{2}$

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
03:31

Problem 69

How many bonds could each of the following chelating ligands form with a metal ion?
a. acetylacetone (acacH), a common ligand in organometallic catalysts:
b. diethylenetriamine, used in a variety of industrial processes:
c. salen, a common ligand for chiral organometallic catalysts:
d. porphine, often used in supermolecular chemistry as well as catalysis; biologically, porphine is the basis for many different types of porphyrin-containing proteins, including heme proteins:

Kevin Chimex
Kevin Chimex
Numerade Educator
11:02

Problem 70

The complex ion Ru(phen) ${ }^{2+}$ has been used as a probe for the structure of DNA. (Phen is a bidentate ligand.)
a. What type of isomerism is found in $\mathrm{Ru}(\mathrm{phen})_{3}^{2+} ?$
b. Ru(phen) $_{3}^{2+}$ is diamagnetic (as are all complex ions of $\mathrm{Ru}^{2+}$ ). Draw the crystal field diagram for the $d$ orbitals in this complex ion.

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
05:21

Problem 71

Hemoglobin (abbreviated $\mathrm{Hb}$ ) is a protein that is responsible for the transport of oxygen in the blood of mammals. Each hemoglobin molecule contains four iron atoms that serve as the binding sites for $\mathrm{O}_{2}$ molecules. The oxygen binding is $\mathrm{pH}$ dependent. The relevant equilibrium reaction is
$$\mathrm{HbH}_{4}{ }^{4+}(a q)+4 \mathrm{O}_{2}(g) \rightleftharpoons \mathrm{Hb}\left(\mathrm{O}_{2}\right)_{4}(a q)+4 \mathrm{H}^{+}(a q)$$
Use Le Châtelier's principle to answer the following.
a. What form of hemoglobin, $\mathrm{HbH}_{4}^{4+}$ or $\mathrm{Hb}\left(\mathrm{O}_{2}\right)_{4}$, is favored in the lungs? What form is favored in the cells?
b. When a person hyperventilates, the concentration of $\mathrm{CO}_{2}$ in the blood decreases. How does this affect the oxygenbinding equilibrium? How does breathing into a paper bag help to counteract this effect? (Hint: $\mathrm{CO}_{2}$ reacts with water to produce carbonic acid.)
c. When a person has suffered a cardiac arrest, an injection of a sodium bicarbonate solution is given. Why is this step necessary?

Cameron Oden
Cameron Oden
Numerade Educator
05:43

Problem 72

Why are $\mathrm{CN}^{-}$ and $\mathrm{CO}$ toxic to humans?

Anupa Sharad Medhekar
Anupa Sharad Medhekar
Numerade Educator
01:42

Problem 73

What causes high-altitude sickness, and what is high-altitude acclimatization?

Arpit Gupta
Arpit Gupta
Numerade Educator
05:17

Problem 74

Ethylenediaminetetraacetate $\left(\mathrm{EDTA}^{4-}\right)$ is used as a complexing agent in chemical analysis with the structure shown in Figure 21.7. Solutions of EDTA $^{4-}$ are used to treat heavy metal poisoning by removing the heavy metal in the form of a soluble complex ion. The complex ion essentially eliminates the heavy metal ions from reacting with biochemical systems. The reaction of EDTA $^{4-}$ with $\mathrm{Pb}^{2+}$ is $\mathrm{Pb}^{2+}(a q)+\mathrm{EDTA}^{4-}(a q) \rightleftharpoons \mathrm{PbEDTA}^{2-}(a q) \quad K=1.1 \times 10^{18}$
Consider a solution with $0.010 \mathrm{~mol} \mathrm{~Pb}\left(\mathrm{NO}_{3}\right)_{2}$ added to $1.0 \mathrm{~L}$ of an aqueous solution buffered at $\mathrm{pH}=13.00$ and containing $0.050$ $M \mathrm{Na}_{4} \mathrm{EDTA} .$ Does $\mathrm{Pb}(\mathrm{OH})_{2}$ precipitate from this solution? $\left(K_{\text {?? }}\right.$ for $\left.\mathrm{Pb}(\mathrm{OH})_{2}=1.2 \times 10^{-15} .\right)$

Susan Hallstrom
Susan Hallstrom
Numerade Educator
04:43

Problem 75

Acetylacetone (see Exercise 69, part a), abbreviated acacH, is a bidentate ligand. It loses a proton and coordinates as acac $^{-}$, as shown below: Acetylacetone reacts with an ethanol solution containing a salt of europium to give a compound that is $40.1 \% \mathrm{C}$ and $4.71 \% \mathrm{H}$ by mass. Combustion of $0.286 \mathrm{~g}$ of the compound gives $0.112 \mathrm{~g}$ $\mathrm{Eu}_{2} \mathrm{O}_{3}$. Assuming the compound contains only $\mathrm{C}, \mathrm{H}, \mathrm{O}$, and $\mathrm{Eu}$, determine the formula of the compound formed from the reaction of acetylacetone and the europium salt. (Assume that the compound contains one europium ion.)

Madi Sousa
Madi Sousa
Numerade Educator
09:02

Problem 76

A transition metal compound contains a cobalt ion, chloride ions, and water molecules. The $\mathrm{H}_{2} \mathrm{O}$ molecules are the ligands in the complex ion and the $\mathrm{Cl}^{-}$ ions are the counterions. $\mathrm{A}$ $0.256-\mathrm{g}$ sample of the compound was dissolved in water, and excess silver nitrate was added. The silver chloride was filtered, dried, and weighed, and it had a mass of $0.308 \mathrm{~g}$. A second sample of $0.416 \mathrm{~g}$ of the compound was dissolved in water, and an excess of sodium hydroxide was added. The hydroxide salt was filtered and heated in a flame, forming cobalt(III) oxide. The mass of cobalt(III) oxide formed was $0.145 \mathrm{~g}$. What is the oxidation state of cobalt in the complex ion and what is the formula of the compound?

Julian Taurozzi
Julian Taurozzi
Numerade Educator
03:16

Problem 77

When aqueous KI is added gradually to mercury(II) nitrate, an orange precipitate forms. Continued addition of KI causes the precipitate to dissolve. Write balanced equations to explain these observations. (Hint: $\mathrm{Hg}^{2+}$ reacts with $\mathrm{I}^{-}$ to form $\mathrm{HgI}_{4}{ }^{2-}$.) Would you expect $\mathrm{HgL}_{4}{ }^{2-}$ to form colored solutions? Explain.

Julian Taurozzi
Julian Taurozzi
Numerade Educator
00:01

Problem 78

In the production of printed circuit boards for the electronics industry, a $0.60-\mathrm{mm}$ layer of copper is laminated onto an insulating plastic board. Next, a circuit pattern made of a chemically resistant polymer is printed on the board. The unwanted copper is removed by chemical etching, and the protective polymer is finally removed by solvents. One etching reaction is
$\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{Cl}_{2}(a q)+4 \mathrm{NH}_{3}(a q)+\mathrm{Cu}(s)$
$\longrightarrow 2\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{Cl}(a q)$
a. Is this reaction an oxidation-reduction process? Explain.
b. $A$ plant needs to manufacture 10,000 printed circuit boards, each $8.0 \times 16.0 \mathrm{~cm}$ in area. An average of $80 . \%$ of the copper is removed from each board (density of copper $=8.96$ $\mathrm{g} / \mathrm{cm}^{3}$ ). What masses of $\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{Cl}_{2}$ and $\mathrm{NH}_{3}$ are needed
to do this? Assume $100 \%$ yield.

Susan Hallstrom
Susan Hallstrom
Numerade Educator
09:47

Problem 79

Use standard reduction potentials to calculate $\mathscr{E}^{\circ}, \Delta G^{\circ}$, and $K$ (at $298 \mathrm{~K}$ ) for the reaction that is used in production of gold:
$$2 \mathrm{Au}(\mathrm{CN})_{2}^{-}(a q)+\mathrm{Zn}(s) \longrightarrow 2 \mathrm{Au}(s)+\mathrm{Zn}(\mathrm{CN})_{4}^{2-}(a q)$$
The relevant half-reactions are
$$\begin{aligned}\mathrm{Au}(\mathrm{CN})_{2}^{-}+\mathrm{e}^{-} \longrightarrow \mathrm{Au}+2 \mathrm{CN}^{-} & \mathscr{C}^{\circ} &=-0.60 \mathrm{~V} \\
\mathrm{Zn}(\mathrm{CN})_{4}^{2-}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Zn}+4 \mathrm{CN}^{-} & \mathscr{E}^{\circ} &=-1.26 \mathrm{~V}
\end{aligned}$$

Kevin Chimex
Kevin Chimex
Numerade Educator
03:13

Problem 80

Until the discoveries of Alfred Werner, it was thought that carbon had to be present in a compound for it to be optically active. Werner prepared the following compound containing $\mathrm{OH}^{-}$ ions as bridging groups and separated the optical isomers.
a. Draw structures of the two optically active isomers of this compound.
b. What are the oxidation states of the cobalt ions?
c. How many unpaired electrons are present if the complex is the low-spin case?

Madi Sousa
Madi Sousa
Numerade Educator
07:00

Problem 81

Draw all the geometrical isomers of $\left[\mathrm{Cr}(\mathrm{en})\left(\mathrm{NH}_{3}\right)_{2} \mathrm{BrCl}\right]^{+} .$
Which of these isomers also have an optical isomer? Draw the various isomers.

Arpit Gupta
Arpit Gupta
Numerade Educator
01:57

Problem 82

A compound related to acetylacetone is $1,1,1$ -trifluoroacetylacetone (abbreviated Htfa):
Htfa forms complexes in a manner similar to acetylacetone. (See Exercise 45.) Both $\mathrm{Be}^{2+}$ and $\mathrm{Cu}^{2+}$ form complexes with tfa $^{-}$ having the formula $\mathrm{M}(\mathrm{tfa})_{2}$. Two isomers are formed for each metal complex.
a. The $\mathrm{Be}^{2+}$ complexes are tetrahedral. Draw the two isomers of Be(tfa) $_{2}$. What type of isomerism is exhibited by $\mathrm{Be}(\mathrm{tfa})_{2} ?$
b. The $\mathrm{Cu}^{2+}$ complexes are square planar. Draw the two isomers of $\mathrm{Cu}(\mathrm{tfa})_{2} .$ What type of isomerism is exhibited by $\mathrm{Cu}(\mathrm{tfa})_{2} ?$

Arpit Gupta
Arpit Gupta
Numerade Educator
03:53

Problem 83

Would it be better to use octahedral $\mathrm{Ni}^{2+}$ complexes or octahedral $\mathrm{Cr}^{2+}$ complexes to determine whether a given ligand is a strong-field or weak-field ligand by measuring the number of unpaired electrons? How else could the relative ligand field strengths be determined?

Madi Sousa
Madi Sousa
Numerade Educator
05:20

Problem 84

Name the following coordination compounds.
a. $\mathrm{Na}_{4}\left[\mathrm{Ni}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)_{3}\right]$
b. $\mathrm{K}_{2}\left[\mathrm{CoCl}_{4}\right]$
c. $\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{SO}_{4}$
d. $\left[\mathrm{Co}(\mathrm{en})_{2}(\mathrm{SCN}) \mathrm{Cl}\right] \mathrm{Cl}$

Arpit Gupta
Arpit Gupta
Numerade Educator
09:48

Problem 85

Give formulas for the following.
a. Hexakis(pyridine)cobalt(III) chloride
b. Pentaammineiodochromium(III) iodide
c. Tris(ethylenediamine)nickel(II) bromide
d. Potassium tetracyanonickelate(II)
e. Tetraamminedichloroplatinum(IV) tetrachloroplatinate(II)

Kevin Chimex
Kevin Chimex
Numerade Educator
02:40

Problem 86

The equilibrium constant $K_{\mathrm{a}}$ for the reaction
$$\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{3+}(a q)+\mathrm{H}_{2} \mathrm{O}(l) \rightleftharpoons$$
is $6.0 \times 10^{-3}$
a. Calculate the $\mathrm{pH}$ of a $0.10 \mathrm{M}$ solution of $\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{3+}$.
b. Will a $1.0 M$ solution of iron(II) nitrate have a higher or lower $\mathrm{pH}$ than a $1.0 \mathrm{M}$ solution of iron(III) nitrate? Explain.

Anatole Borisov
Anatole Borisov
Numerade Educator
03:21

Problem 87

Carbon monoxide is toxic because it binds more strongly to iron in hemoglobin (Hb) than does $\mathrm{O}_{2}$. Consider the following reactions and approximate standard free energy changes:
$$\begin{array}{cl}\mathrm{Hb}+\mathrm{O}_{2} \longrightarrow \mathrm{HbO}_{2} & \Delta G^{\circ}=-70 \mathrm{~kJ} \\
\mathrm{Hb}+\mathrm{CO} \longrightarrow \mathrm{HbCO} & \Delta G^{\circ}=-80 \mathrm{~kJ}\end{array}$$
Using these data, estimate the equilibrium constant value at $25^{\circ} \mathrm{C}$ for the following reaction:
$$\mathrm{HbO}_{2}+\mathrm{CO} \rightleftharpoons \mathrm{HbCO}+\mathrm{O}_{2}$$

Julian Taurozzi
Julian Taurozzi
Numerade Educator
02:58

Problem 88

For the process
$$\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{2+}+\mathrm{Cl}^{-} \longrightarrow \mathrm{Co}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}^{+}+\mathrm{NH}_{3}$$
what would be the expected ratio of cis to trans isomers in the product?

Cameron Oden
Cameron Oden
Numerade Educator
00:02

Problem 89

The complex trans-[NiA $\left._{2} \mathrm{~B}_{4}\right]^{2+}$, where $\mathrm{A}$ and $\mathrm{B}$ represent neutral ligands, is known to be diamagnetic. Do $\mathrm{A}$ and $\mathrm{B}$ produce very similar or very different crystal fields? Explain.

Susan Hallstrom
Susan Hallstrom
Numerade Educator
13:27

Problem 90

Impure nickel, refined by smelting sulfide ores in a blast furnace, can be converted into metal from $99.90 \%$ to $99.99 \%$ purity by the Mond process. The primary reaction involved in the Mond process is
$$\mathrm{Ni}(s)+4 \mathrm{CO}(g) \rightleftharpoons \mathrm{Ni}(\mathrm{CO})_{4}(g)$$
a. Without referring to Appendix 4 , predict the sign of $\Delta S^{\circ}$ for the preceding reaction. Explain.
b. The spontaneity of the preceding reaction is temperature dependent. Predict the sign of $\Delta S_{\text {sum }}$ for this reaction. Explain.
c. For $\mathrm{Ni}(\mathrm{CO})_{4}(g), \Delta H_{\mathrm{f}}^{\circ}=-607 \mathrm{~kJ} / \mathrm{mol}$ and $S^{\circ}=417 \mathrm{~J} / \mathrm{K} \cdot \mathrm{mol}$
at $298 \mathrm{~K}$. Using these values and data in Appendix 4, calculate $\Delta H^{\circ}$ and $\Delta S^{\circ}$ for the preceding reaction.
d. Calculate the temperature at which $\Delta G^{\circ}=0(K=1)$ for the preceding reaction, assuming that $\Delta H^{\circ}$ and $\Delta S^{\circ}$ do not depend on temperature.
e. The first step of the Mond process involves equilibrating impure nickel with $\mathrm{CO}(g)$ and $\mathrm{Ni}(\mathrm{CO})_{4}(g)$ at about $50^{\circ} \mathrm{C}$. The purpose of this step is to convert as much nickel as possible into the gas phase. Calculate the equilibrium constant for the preceding reaction at $50 .{ }^{\circ} \mathrm{C}$.
f. In the second step of the Mond process, the gaseous $\mathrm{Ni}(\mathrm{CO})_{4}$ is isolated and heated at $227^{\circ} \mathrm{C}$. The purpose of this step is to deposit as much nickel as possible as pure solid (the reverse of the preceding reaction). Calculate the equilibrium constant for the above reaction at $227^{\circ} \mathrm{C}$.
g. Why is temperature increased for the second step of the Mond process?

Susan Hallstrom
Susan Hallstrom
Numerade Educator
12:09

Problem 91

Consider the following data:
$$\begin{aligned}
\mathrm{Co}^{3+}+\mathrm{e}^{-} \longrightarrow \mathrm{Co}^{2+} & & \mathscr{E}^{\circ}=1.82 \mathrm{~V} \\
\mathrm{Co}^{2+}+3 \mathrm{en} \longrightarrow \mathrm{Co}(\mathrm{en})_{3}^{2+} & K &=1.5 \times 10^{12} \\
\mathrm{Co}^{3+}+3 \mathrm{en} \longrightarrow \mathrm{Co}(\mathrm{en}){ }^{3+} & K &=2.0 \times 10^{47}
\end{aligned}$$
where en $=$ ethylenediamine.
a. Calculate $\mathscr{E}^{\circ}$ for the half-reaction
$$\mathrm{Co}(\mathrm{en})_{3}^{3+}+\mathrm{e}^{-} \longrightarrow \mathrm{Co}(\mathrm{en})_{3}^{2+}$$
b. Based on your answer to part a, which is the stronger oxidizing agent, $\mathrm{Co}^{3+}$ or $\mathrm{Co}(\mathrm{en})_{3}{ }^{3+}$ ?
c. Use the crystal field model to rationalize the result in part b.

Ronald Prasad
Ronald Prasad
Numerade Educator
00:02

Problem 92

Henry Taube, 1983 Nobel Prize winner in chemistry, has studied the mechanisms of the oxidation-reduction reactions of transition metal complexes. In one experiment he and his students studied the following reaction:
$\begin{aligned} \mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}^{2+}(a q)+& \mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Cl}^{2+}(a q) \\ \longrightarrow & \mathrm{Cr}(\mathrm{III}) \text { complexes }+\mathrm{Co}(\mathrm{II}) \text { complexes } \end{aligned}$
Chromium(III) and cobalt(III) complexes are substitutionally inert (no exchange of ligands) under conditions of the experiment. Chromium(II) and cobalt(II) complexes can exchange ligands very rapidly. One of the products of the reaction is $\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{5} \mathrm{Cl}^{2+} .$ Is this consistent with the reaction proceeding through formation of $\left(\mathrm{H}_{2} \mathrm{O}\right)_{5} \mathrm{Cr}-\mathrm{Cl}-\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5}$ as an intermediate? Explain.

Susan Hallstrom
Susan Hallstrom
Numerade Educator
00:01

Problem 93

Chelating ligands often form more stable complex ions than the corresponding monodentate ligands with the same donor atoms. For example, This increased stability is called the chelate effect. Based on bond energies, would you expect the enthalpy changes for the above reactions to be very different? What is the order (from least favorable to most favorable) of the entropy changes for the above reactions? How do the values of the formation constants correlate with $\Delta S^{\circ} ?$ How can this be used to explain the chelate effect?

Susan Hallstrom
Susan Hallstrom
Numerade Educator
04:50

Problem 94

Qualitatively draw the crystal field splitting of the $d$ orbitals in a trigonal planar complex ion. (Let the $z$ axis be perpendicular to the plane of the complex.)

Cameron Oden
Cameron Oden
Numerade Educator
02:13

Problem 95

Qualitatively draw the crystal field splitting for a trigonal bipyramidal complex ion. (Let the $z$ axis be perpendicular to the trigonal plane.)

Madi Sousa
Madi Sousa
Numerade Educator
00:01

Problem 96

Sketch a $d$ -orbital energy diagram for the following.
a. a linear complex with ligands on the $x$ axis
b. a linear complex with ligands on the $y$ axis

Susan Hallstrom
Susan Hallstrom
Numerade Educator
03:19

Problem 97

Sketch and explain the most likely pattem for the crystal field diagram for the complex ion trans-diamminetetracyanonickelate(II), where $\mathrm{CN}^{-}$ produces a much stronger crystal field than $\mathrm{NH}_{3}$. Explain completely and label the $d$ orbitals in your diagram. Assume the $\mathrm{NH}_{3}$ ligands lie on the $z$ axis.

Susan Hallstrom
Susan Hallstrom
Numerade Educator
06:42

Problem 98

a. Calculate the molar solubility of AgBr in pure water. $K_{\text {sp }}$ for AgBr is $5.0 \times 10^{-13}$
b. Calculate the molar solubility of AgBr in $3.0 M \mathrm{NH}_{3}$. The overall formation constant for $\mathrm{Ag}\left(\mathrm{NH}_{3}\right)_{2}^{+}$ is $1.7 \times 10^{7}$, that is,
$\mathrm{Ag}^{+}(a q)+2 \mathrm{NH}_{3}(a q) \longrightarrow \mathrm{Ag}\left(\mathrm{NH}_{3}\right)_{2}^{+}(a q) \quad K=1.7 \times 10^{7}$
c. Compare the calculated solubilities from parts a and b. Explain any differences.
d. What mass of $\mathrm{AgBr}$ will dissolve in $250.0 \mathrm{~mL}$ of $3.0 \mathrm{M} \mathrm{NH}_{3}$ ?
e. What effect does adding $\mathrm{HNO}_{3}$ have on the solubilities calculated in parts a and $\mathrm{b}$ ?

Aadit Sharma
Aadit Sharma
Numerade Educator
04:26

Problem 99

The ferrate ion, $\mathrm{FeO}_{4}{ }^{2-}$, is such a powerful oxidizing agent that in acidic solution, aqueous ammonia is reduced to elemental nitrogen along with the formation of the iron(III) ion.
a. What is the oxidation state of iron in $\mathrm{FeO}_{4}{ }^{2-}$, and what is the electron configuration of iron in this polyatomic ion? b. If $25.0 \mathrm{~mL}$ of a $0.243 \mathrm{M} \mathrm{FeO}_{4}^{2-}$ solution is allowed to react with $55.0 \mathrm{~mL}$ of $1.45 M$ aqueous ammonia, what volume of nitrogen gas can form at $25^{\circ} \mathrm{C}$ and $1.50 \mathrm{~atm}$ ?

Ronald Prasad
Ronald Prasad
Numerade Educator
00:01

Problem 100

a. In the absorption spectrum of the complex ion [Cr(NCS) $\left._{6}\right]^{3-}$, there is a band corresponding to the absorption of a photon of light with an energy of $1.75 \times 10^{4} \mathrm{~cm}^{-1}$. Given $1 \mathrm{~cm}^{-1}=$ $1.986 \times 10^{-23} \mathrm{~J}$, what is the wavelength of this photon?
b. The $\mathrm{Cr}-\mathrm{N}-\mathrm{C}$ bond angle in $\left[\mathrm{Cr}(\mathrm{NCS})_{6}\right]^{3-}$ is predicted to be $180^{\circ}$. What is the hybridization of the $\mathrm{N}$ atom in the $\mathrm{NCS}^{-}$ ligand when a Lewis acid-base reaction occurs between $\mathrm{Cr}^{3+}$ and $\mathrm{NCS}^{-}$ that would give a $180^{\circ} \mathrm{Cr}-\mathrm{N}-\mathrm{C}$ bond angle? $\left[\mathrm{Cr}(\mathrm{NCS})_{6}\right]^{3-}$ undergoes substitution by ethylenediammine (en) according to the equation
$\left[\mathrm{Cr}(\mathrm{NCS})_{6}\right]^{3-}+2 \mathrm{en} \longrightarrow\left[\mathrm{Cr}(\mathrm{NCS})_{2}(\mathrm{en})_{2}\right]^{+}+4 \mathrm{NCS}^{-}$
Does $\left[\mathrm{Cr}(\mathrm{NCS})_{2}(\mathrm{en})_{2}\right]^{+}$ exhibit geometric isomerism? Does $\left[\mathrm{Cr}(\mathrm{NCS})_{2}(\mathrm{en})_{2}\right]^{+}$ exhibit optical isomerism?

Susan Hallstrom
Susan Hallstrom
Numerade Educator
06:56

Problem 101

Ammonia and potassium iodide solutions are added to an aqueous solution of $\mathrm{Cr}\left(\mathrm{NO}_{3}\right)_{3} .$ A solid is isolated (compound $\mathrm{A}$ ), and the following data are collected:
i. When $0.105 \mathrm{~g}$ of compound $\mathrm{A}$ was strongly heated in excess $\mathrm{O}_{2}, 0.0203 \mathrm{~g} \mathrm{CrO}_{3}$ was formed.
ii. In a second experiment it took $32.93 \mathrm{~mL}$ of $0.100 \mathrm{M} \mathrm{HCl}$ to titrate completely the $\mathrm{NH}_{3}$ present in $0.341 \mathrm{~g}$ compound $\mathrm{A}$.
iii. Compound A was found to contain $73.53 \%$ iodine by mass. iv. The freezing point of water was lowered by $0.64^{\circ} \mathrm{C}$ when $0.601$ g compound $A$ was dissolved in $10.00 \mathrm{~g} \mathrm{H}_{2} \mathrm{O}$ $\left(K_{\mathrm{f}}=1.86^{\circ} \mathrm{C} \cdot \mathrm{kg} / \mathrm{mol}\right)$
What is the formula of the compound? What is the structure of the complex ion present? (Hints: $\mathrm{Cr}^{3+}$ is expected to be sixcoordinate, with $\mathrm{NH}_{3}$ and possibly $\mathrm{I}^{-}$ as ligands. The $\mathrm{I}^{-}$ ions will be the counterions if needed.)

Madi Sousa
Madi Sousa
Numerade Educator
18:44

Problem 102

There are three salts that contain complex ions of chromium and have the molecular formula $\mathrm{CrCl}_{3} \cdot 6 \mathrm{H}_{2} \mathrm{O}$. Treating $0.27 \mathrm{~g}$ of the first salt with a strong dehydrating agent resulted in a mass loss of $0.036 \mathrm{~g}$. Treating $270 \mathrm{mg}$ of the second salt with the same dehydrating agent resulted in a mass loss of $18 \mathrm{mg}$. The third salt did not lose any mass when treated with the same dehydrating agent. Addition of excess aqueous silver nitrate to $100.0-\mathrm{mL}$ portions of $0.100 M$ solutions of each salt resulted in the formation of different masses of silver chloride; one solution yielded 1430 $\mathrm{mg} \mathrm{AgCl} ;$ another, $2870 \mathrm{mg} \mathrm{AgCl}$; the third, $4300 \mathrm{mg} \mathrm{AgCl}$. Two
of the salts are green and one is violet. Suggest probable structural formulas for these salts, defending your answer on the basis of the preceding observations. State which salt is most likely to be violet. Would a study of the magnetic properties of the salts be helpful in determining the structural formulas? Explain.

Susan Hallstrom
Susan Hallstrom
Numerade Educator