Nickel(II) complexes with the formula NiX₂L₂, where X is Cl^- or N-bonded NCS^- and L is the monodentate triphenylphosphine ligand P(C₆H₅)₃, can be square planar or tetrahedral.

(b) If NiCl₂L₂ is paramagnetic and Ni(NCS)₂L₂ is diamagnetic, which of the two complexes is tetrahedral and which is square planar?

For each of the following complexes, draw a crystal field energy-level diagram, assign the electrons to orbitals, and predict the number of unpaired electrons.

(b) [MnCl4]2- (tetrahedral)

Cobalt(III) trifluoroacetylacetonate, Co(tfac)₃, is a sixcoordinate, octahedral metal chelate in which three planar, bidentate tfac ligands are attached to a central Co atom:

(b) Diastereoisomers A and B have dipole moments of 6.5 D and 3.8 D, respectively. Which of your diastereoisomers is A and which is B?

Tell how many diastereoisomers are possible for each of the following complexes, and draw their structures. 

(c) [Cu(H₂O)₄Cl₂]⁺

(d) Ru(NH₃)₃I₃

Predict the number of unpaired electrons for each of the following.

(c) Mn3+

(d) Cr2+

Give a valence bond description of the bonding in each of the following complexes. Include orbital diagrams for the free metal ion and the metal ion in the complex. Indicate which hybrid orbitals the metal ion uses for bonding, and specify the number of unpaired electrons. 

(b) [NiBr₄]^2- (tetrahedral) 

Look at the location in the periodic table of elements A, B, C, and D. What is the electron configuration of the transition metal in each of the following ions?  

(a) A²⁺

(b) B⁺

For each of the following complexes, describe the bonding using valence bond theory. Include orbital diagrams for the free metal ion and the metal ion in the complex. Indicate which hybrid orbitals the metal ion uses for bonding, and specify the number of unpaired electrons. 

(b) [Ag(NH3)2]+

Assign a systematic name to each of the following ions.

(c) [Fe(H₂O)₅NCS]²⁺

(d) [Cr(NH₃)₂(C₂O₄)₂]^-

What is the systematic name for each of the following ions? 

(c) [Co(CO₃)₃]^3-

(d) [Pt(en)₂(SCN)₂]²⁺

For each of the following complexes, draw a crystal field energy-level diagram, assign the electrons to orbitals, and predict the number of unpaired electrons.

(c) [Co(NCS)4]2- (tetrahedral)

Nickel(II) complexes with the formula NiX₂L₂, where X is Cl^- or N-bonded NCS^- and L is the monodentate triphenylphosphine ligand P(C₆H₅)₃, can be square planar or tetrahedral.

(c) Draw possible structures for each of the NiX₂L₂ complexes, and tell which ones have a dipole moment.

Spinach contains a lot of iron but is not a good source of dietary iron because nearly all the iron is tied up in the oxalate complex [Fe(C₂O₄)₃]^3-.

(c) Draw a crystal field energy-level diagram for [Fe(C₂O₄)₃]^3-, and predict the number of unpaired electrons. (C₂O₄^2- is a weak-field bidentate ligand.)

The percent iron in iron ore can be determined by dissolving the ore in acid, then reducing the iron to Fe2+, and finally titrating the Fe2+ with aqueous KMnO4. The reaction products are Fe2+ and Mn2+.

(c) Draw a crystal field energy-level diagram for the reactants and products, MnO4-, 3Fe1H2O2642+, 3Fe1H2O2643+, and 3Mn1H2O2642+, and predict the number of unpaired electrons for each.

Cobalt(III) trifluoroacetylacetonate, Co1tfac23, is a sixcoordinate, octahedral metal chelate in which three planar, bidentate tfac ligands are attached to a central Co atom:

(d) Draw a crystal field energy-level diagram for Co1tfac23, and predict its magnetic properties. (In this complex, tfac is a strong-field ligand.)

In acidic aqueous solution, the complex trans-[Co(en)₂Cl₁]²⁺(aq) undergoes the following substitution reaction:

trans-[Co(en)₁Cl₂]⁺(aq) + H₂O(l) → trans-[Co(en)₂(H₂O)Cl]²⁺(aq) + Cl^–(aq)

The reaction is first order in trans-[Co(en)₂Cl₂]⁺(aq), and the rate constant at 25°C is 3.2×10^–5 s^–1.

(d) Is the reaction product chiral or achiral? Explain.

Spinach contains a lot of iron but is not a good source of dietary iron because nearly all the iron is tied up in the oxalate complex [Fe(C₂O₄)₃]^3-.

(d) Draw the structure of [Fe(C₂O₄)₃]^3-. Is the complex chiral or achiral?

The complete reaction of 2.60 g of chromium metal with 50.00 mL of 1.200 M H2SO4 in the absence of air gave a blue solution and a colorless gas that was collected at 25°C and a pressure of 735 mm Hg. (e) When an excess of KCN is added to the solution, the color changes, and the paramagnetism of the solution

decreases. Explain.

In acidic aqueous solution, the complex trans-[Co(en)₂Cl₁]²⁺(aq) undergoes the following substitution reaction:

trans-[Co(en)₂Cl₁]⁺(aq) + H₂O(l) → trans-[Co(en)₂(H₂O)Cl]²⁺(aq) + Cl^–(aq)

The reaction is first order in trans-[Co(en)₂Cl₂]⁺(aq), and the rate constant at 25°C is 3.2×10^–5 s^–1.

e. Draw a crystal field energy-level diagram for ​trans-[Co(en)₂Cl₂]⁺ that takes account of the fact that Cl^– is a weaker-field ligand than ethylenediamine.

Locate on the periodic table the transition elements with the following electron configurations. Identify each element.

(a) [Ar] 3d74s2

(b) [Ar] 3d54s1

Locate on the periodic table the transition elements with the following electron configurations. Identify each element.

(c) [Kr] 4d25s2

(d) [Xe] 4f36s2

Look at the location in the periodic table of elements A, B, C, and D. What is the electron configuration of the transition metal in each of the following ions?

(c) C3+

(d) DO42-

What is the systematic name for each of the following molecules or ions? Include cis or trans prefixes for diastereoisomers. Platinum is Pt(II) in square planar complexes and Pt(IV) in octahedral complexes.

(1)

(2)

(3)

(4)

Consider the following isomers [Cr(NH3)2Cl4]-.

(a) Label the isomers as cis or trans.

(b) Which isomers are identical, and which are different?

(c) Do any of these isomers exist as enantiomers? Explain.

Consider the following ethylenediamine complexes.

(a) Which complexes are chiral, and which are achiral?

(b) Draw the enantiomer of each chiral complex.

(c) Which, if any, of the chiral complexes are enantiomers of one another?

Consider the following ethylenediamine complexes.

(a) Which complexes are chiral, and which are achiral?

(b) Draw the enantiomer of each chiral complex.

(c) Which, if any, of the chiral complexes are enantiomers of one another?

Consider the following ethylenediamine complexes.

(a) Which complexes are chiral, and which are achiral?

(b) Draw the enantiomer of each chiral complex.

(c) Which, if any, of the chiral complexes are enantiomers of one another?

Use the periodic table to give the electron configuration for each of the following atoms and ions. 

(c) Co(V) in CoO₄^3–

(d) Co(IV) in CoF₆^2–

Titanium, used to make jet aircraft engines, is much harder than potassium or calcium. Explain.