The Transition Elements and Their Coordination Compounds

Give systematic names for the following formulas:

(a)  $\mathbf{\text{K}}\left[\text{Pt}\left({\text{NH}}_3\right){\text{Cl}}_5\right]$

(b) $\left[\text{Cu}\left(\text{en}\right){\left({\text{NH}}_3\right)}_2\right]\left[\text{Co}\left(\mathrm{en}\right){\text{Cl}}_4\right]$

(c)$\left[\text{Pt}{\left(\text{en}\right)}_2{\text{Br}}_2\right]{\left({\text{ClO}}_4\right)}_{\mathbf{2}}$

As a fuel, H₂(g) produces only nonpolluting   when it burns. Moreover, it combines with O₂(g) in a fuel cell (Chapter 21) to provide electrical energy.

(a) Calculate $\mathbf{△}{\mathbf{H}}^{\mathbf{°}}\mathbf{,}\mathbf{△}{\mathbf{S}}^{\mathbf{°}}$and $\mathbf{△}{\mathbf{G}}^{\mathbf{°}}$per mole of   at 298 K.

(b) Is the spontaneity of this reaction dependent on T? Explain.

(c) At what temperature does the reaction become spontaneous?

What are the coordination number of the metal ion and the number of individual ions per formula unit in each of the compounds in Problem 23.63?

What is the coordination number of the metal ion and the number of individual ions per formula unit in each of the compounds in Problem 23.64?

Give the coordination number of the metal ion and the number of ions per formula unit in each compound in Problem 23.67.

Which of these ligands can participate in linkage isomerism?

1. ${\mathbf{\text{NO}}}_{\mathbf{2}}^{\mathbf{-}}$
   
2. ${\mathbf{\text{SO}}}_{\mathbf{2}}$
   
3. ${\mathbf{\text{NO}}}_{\mathbf{3}}^{\mathbf{-}}$
   

 Explain with Lewis structures.

Which of these ligands can participate in linkage isomerism?

(a) SCN^-

(b)S₂O₃^2- (thiosulfate)

(c) HS^-

 Explain with Lewis structures.

For any of the following that can exist as isomers, state the type of isomerism and draw the structures:

1. [Pt(CH₃NH₂)₂Br₂] 
2. [Pt(NH₃)₂FCl]  
3. [Pt(H₂O)(NH₃)FCl]

For any of the following that can exist as isomers, state the type of isomerism and draw the structures:

(a) [Zn(en)F₂]

(b) [Zn(H₂O)(NH₃)FCl] 

(c) [Pd(CN)₂(OH)₂] ^2-

For any of the following that can exist as isomers, state the type of isomerism and draw the structures:

1. ^- $\left[\mathbf{PtCl}\mathbf{2}\mathbf{Br}\mathbf{2}\right]\mathbf{2}$
2. ^{-$\left[\mathbf{Cr}\left(\mathbf{NH}\mathbf{3}\right)\mathbf{5}\left(\mathbf{NO}\mathbf{2}\right)\right]\mathbf{2}$}
3. ^{-$\left[\mathbf{Pt}\left(\mathbf{NH}\mathbf{3}\right)\mathbf{4}\mathbf{I}\mathbf{2}\right]\mathbf{2}$}

For any of the following that can exist as isomers, state the type of isomerism and draw the structures:

[CO(NH₃)₅Cl]Br₂ 

[Pt(CH₃NH₂)₃Cl]Br 

[Fe(H₂O)(NH₃)₂] ²⁺

Chromium(III), like cobalt(III), has a coordination number of 6 in many of its complex ions. Compounds are known that have the traditional formula CrCl3_nNH3, where n = 3 to 6. Which of the compounds has an electrical conductivity in an aqueous solution similar to that of an equimolar NaCl solution?

When MCl₄(NH₃)₂ is dissolved in water and treated with AgNO₃, 2 mol of AgCl precipitates immediately for each mole of MCl₄(NH₃)₂. Give the coordination number of M in the complex.

Palladium, like its group neighbor platinum, forms four coordinate Pd(II) and six-coordinate Pd(IV) complexes. Write

modern formulas for the complexes with these compositions:

(a) PdK(NH₃)Cl₃                                                   (b) PdCl₂(NH₃)₂

(c) PdK₂Cl₆                                                         

(d) Pd(NH₃)₄Cl₄

(a) What is a coordinate covalent bond?

(b) Is it involved when FeCl₃ dissolves in water? Explain.

(c) Is it involved when HCl gas dissolves in water? Explain.

According to valence bond theory, what set of orbitals is used by a Period 4 metal ion in forming 

(a) a square planar complex 

(b) a tetrahedral complex

A metal ion uses d²sp³ orbitals when forming a complex. What is its coordination number and the shape of the complex?

A metal ion uses d²sp³ orbitals when forming a complex. What is its coordination number and the shape of the complex?

:Some  ${}_{\mathbf{95}}{}^{\mathbf{243}}\mathbf{Am}$ was present when Earth formed, but it all decayed in the next billion years. The first three steps in this decay series are the emission of an $\mathbf{\alpha }$ particle, a   particle, and another ${\mathbf{\beta }}^{\mathbf{-}}$particle. What other isotopes were present on the young Earth in a rock that contained some ${}_{\mathbf{95}}{}^{\mathbf{243}}\mathbf{Am}$?

Which of these ions cannot form both high- spin and low-spin octahedral complexes: (a) ${\mathbf{Mn}}^{\mathbf{3}\mathbf{+}}\mathbf{;}$(b)${\mathbf{Nb}}^{\mathbf{3}\mathbf{+}}\mathbf{;}$(c)^{${\mathbf{Ru}}^{\mathbf{3}\mathbf{+}}\mathbf{;}$} (d)  ${\mathbf{Ni}}^{\mathbf{2}\mathbf{+}}$

Draw orbital-energy splitting diagrams and use the spectrochemical series to show the orbital occupancy for each of the following (assuming that $\mathbf{\left(}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{\right)}$ is a weak-field ligand): $\mathbf{\left(}\mathbf{a}\mathbf{\right)}{\mathbf{\left[}\mathbf{Cr}{\left(H_{2}O\right)}_{\mathbf{6}}\mathbf{\right]}}^{\mathbf{3}\mathbf{+}}\mathbf{\left(}\mathbf{b}\mathbf{\right)}{\mathbf{\left[}\mathbf{Cu}{\left(H_{2}O\right)}_{\mathbf{4}}\mathbf{\right]}}^{\mathbf{2}\mathbf{+}}\mathbf{\left(}\mathbf{c}\mathbf{\right)}{\mathbf{\left[}{\mathbf{FeF}}_{\mathbf{6}}\mathbf{\right]}}^{\mathbf{3}\mathbf{-}}$

Draw orbital-energy splitting diagrams and use the spectrochemical series to show the orbital occupancy for each of the following (assuming that is a weak-field ligand):

$\mathbf{a}\mathbf{)}\mathbf{ }{\left[\mathrm{Cr}{\left(\mathrm{CN}\right)}_6\right]}^{\mathbf{3}\mathbf{-}}\mathbf{ }\mathbf{b}\mathbf{)}\mathbf{ }{\left[\mathrm{Rh}{\left(\mathrm{CO}\right)}_6\right]}^{\mathbf{3}\mathbf{+}}\mathbf{ }\mathbf{c}\mathbf{)}{\left[\mathrm{Co}{\left(\mathrm{OH}\right)}_6\right]}^{\mathbf{4}\mathbf{-}}$

Draw orbital-energy splitting diagrams and use the spectrochemical series to show the orbital occupancy for each of the following (assuming that is a weak-field ligand):

Rank the following in order of increasing $\mathbf{∆}$ and energy of light absorbed: ${\mathbf{\left[}\mathbf{Cr}{\left({\mathrm{NH}}_3\right)}_{\mathbf{6}}\mathbf{\right]}}^{\mathbf{3}\mathbf{+}}\mathbf{,}{\mathbf{\left[}\mathbf{Cr}{\left(H_{2}O\right)}_{\mathbf{6}}\mathbf{\right]}}^{\mathbf{3}\mathbf{+}}\mathbf{,}{\mathbf{\left[}\mathbf{Cr}{\left({\mathrm{NO}}_2\right)}_{\mathbf{6}}\mathbf{\right]}}^{\mathbf{3}\mathbf{+}}$

Rank the following in order of decreasing $(∆)$ and energy of light absorbed: ${\left[\mathrm{Cr}{\left(\mathrm{en}\right)}_3\right]}^{\mathbf{3}\mathbf{+}}\mathbf{,}{\left[\mathrm{Cr}{\left(\mathrm{CN}\right)}_6\right]}^{\mathbf{3}\mathbf{-}}\mathbf{,}{\left[{\mathrm{CrCl}}_6\right]}^{\mathbf{3}\mathbf{-}}$

Cosmologists modeling the origin of the elements postulate nuclides with very short half-lives. One of these nuclides, ${}^{\mathbf{8}}\mathbf{Be}\left(t_{1/2}=7\times {10}^{-17} s\right)$, plays a key role in stellar nucleosynthesis (p. 1099) because it must fuse with ${}^{\mathbf{4}}\mathbf{He}$ to form ${}^{\mathbf{12}}\mathbf{C}$ before decaying. Another explanation involves the simultaneous fusion of three ${}^{\mathbf{4}}\mathbf{He}$ nuclei to form ${}^{\mathbf{12}}\mathbf{C}$. Comment on the validity of this alternative mechanism.

Question: Correct each name that has an error:

(a)  $\mathbf{Na}\mathbf{\left[}{\mathbf{FeBr}}_{\mathbf{4}}\mathbf{\right]}$ sodium tetrabromoferrate(II)

(b)  ${\left[\mathrm{Ni}{\left({\mathrm{NH}}_3\right)}_6\right]}^{\mathbf{2}\mathbf{-}}$nickel hexaammine ion

(c)  $\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_3{I}_3\right]$ triamminetriiodocobalt(III)

(d)  ${\left[V{\left(\mathrm{CN}\right)}_6\right]}^{\mathbf{3}\mathbf{-}}$ hexacyanovanadium(III) ion

(e)  $\mathbf{K}\left[{\mathrm{FeCl}}_4\right]$potassium tetrachloroiron(III)

Question: Write the general electron configuration of a transition element

 (a) In Period 5;

 (b) In Period 6.

Question: What is the general rule concerning the order in which electrons are removed from a transition metal atom to form an ion? Give an example from Group 5B $\left(5\right)$. Name two types of measurements used to study electron configurations of ions.

Question: (a) What is the lanthanide contraction? 

(b) How does it affect atomic size down a group of transition elements? 

(c) How does it influence the densities of the Period 6 transition elements?

Question: (a) What behaviour distinguishes paramagnetic and diamagnetic substances? 

(b) Why are paramagnetic ions common among transition elements but not main-group elements?

(c) Why are coloured solutions of metal ions common among transition elements but not main-group elements?

Question: Using the periodic table to locate each element, write the electron configuration of (a) V (b) Y (c) Hg.

Question: Using the periodic table to locate each element, write the electron configuration of (a) Ru; (b) Cu; (c) Ni.

Question: Using the periodic table to locate each element, write theelectron configuration of (a) Os (b) Co (c) Ag.

Question: Using the periodic table to locate each element, write the electron configuration of (a) Zn (b) Mn (c) Re.

Question: Give the electron configuration and the number of unpaired electrons for $\left(a\right)\mathbf{ }{\mathbf{Sc}}^{\mathbf{+}\mathbf{3}}\mathbf{ }\left(b\right)\mathbf{ }{\mathbf{Cu}}^{\mathbf{+}\mathbf{2}}\mathbf{ }\left(c\right)\mathbf{ }{\mathbf{Fe}}^{\mathbf{+}\mathbf{3}}\mathbf{ }\left(d\right)\mathbf{ }{\mathbf{Nb}}^{\mathbf{+}\mathbf{3}}$

Question: Give the electron configuration and the number of unpaired

electrons for: $\left(a\right)\mathbf{ }{\mathbf{Cr}}^{\mathbf{+}\mathbf{3}}\mathbf{ }\left(b\right)\mathbf{ }{\mathbf{Ti}}^{\mathbf{+}\mathbf{4}}\mathbf{ }\left(c\right)\mathbf{ }{\mathbf{Co}}^{\mathbf{+}\mathbf{3}}\mathbf{ }\left(d\right)\mathbf{ }{\mathbf{Ta}}^{\mathbf{+}\mathbf{2}}$

In which compound does Cr exhibit greater metallic behaviour, CrF₂ or CrF₆? Explain.

Is it more difficult to oxidize Cr or Mo? Explain.

The green patina of Cu-alloy roofs results from corrosion in the presence of ${\mathbf{O}}_{\mathbf{2}}\mathbf{,}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{,}{\mathbf{CO}}_{\mathbf{2}}$, and sulfur compounds. The other members of Group 1B(11) Ag and Au, do not form a patina. Corrosion of Cu and Ag in the presence of sulfur compounds leads to a black tarnish, but Au does not tarnish. This pattern is different from that in Group 1A(1), where ease of oxidation increases down the group. Explain these different group patterns.

(a) What is the maximum number of unpaired electrons in a lanthanide ion? (b) How does this number relate to the occupancy of the 4f sub-shell?

What atomic property of the lanthanides leads to their remarkably similar chemical properties?

Which of the actinides are radioactive?

Give the electron configuration of (a) La; (b) Ce³⁺ (c) Es; (d) U⁴⁺.

Give the electron configuration of (a) Pm  (b) Lu³⁺ (c) Th  (d) Fm³⁺

Only a few lanthanides show an oxidation state other than +3. Two of these, europium (Eu) and terbium (Tb), are found near the middle of the series, and their unusual oxidation states can be associated with a half-filled f subshell.

(a) Write the electron configurations of Eu²⁺, Eu³⁺, and Eu⁴⁺. Why is Eu²⁺ a common ion, whereas Eu⁴⁺ is unknown?

(b) Write the electron configurations of Tb²⁺, Tb³⁺, and Tb⁴⁺. Would you expect Tb to show a +2 or a +4 oxidation state? Explain

Which lanthanide has the maximum number of unpaired electrons in both its atom and 3+ ion? Give the number of unpaired electrons in the atom and ion.

Why is chromium so useful for decorative electroplating?

What is valence-state electronegativity? Explain the change in acidity of the oxides of Mn with changing O.N. of the metal.

What property does manganese confer to steel?