Textbook Question
Complete the exercises below. Draw the crystal-field energy-level diagrams and show the placement of electrons for each of the following complexes:
a. [VCl6]3–,
b. [FeF6]3– (a high-spin complex),
Ch.23 - Transition Metals and Coordination Chemistry
Chapter 23, Problem 2
Draw the structure for Pt (en) Cl₂ and use it to answer the following questions: a. What is the coordination number for platinum in this complex? b. What is the coordination geometry? c. What is the oxidation state of the platinum? d. How many unpaired electrons are there? [Find more in Sections 23.2 and 23.6.]
Verified step by step guidance1
Step 1: Identify the components of the complex. The complex is Pt(en)Cl₂, where 'en' stands for ethylenediamine, a bidentate ligand, and Cl represents chloride ions.
Step 2: Determine the coordination number. The coordination number is the number of ligand atoms directly bonded to the central metal. Ethylenediamine (en) is a bidentate ligand, meaning it forms two bonds with the metal. With two chloride ions, the total coordination number is 4.
Step 3: Determine the coordination geometry. For a coordination number of 4, the possible geometries are square planar or tetrahedral. Platinum(II) complexes, like Pt(en)Cl₂, typically adopt a square planar geometry.
Step 4: Calculate the oxidation state of platinum. Assign oxidation states to the ligands: ethylenediamine is neutral, and each chloride ion has a -1 charge. Let the oxidation state of Pt be x. The equation is x + 0 + 2(-1) = 0, solving for x gives the oxidation state of Pt.
Step 5: Determine the number of unpaired electrons. Platinum in a square planar complex with an oxidation state of +2 typically has a d⁸ electron configuration. In a square planar field, the d orbitals split such that there are no unpaired electrons.
Related Practice
Textbook Question
The coordination complex [Cr(CO)6] forms colorless, diamagnetic crystals that melt at 90 °C
a. What is the oxidation number of chromium in this compound?
d. Write the name for [Cr(CO)6] using the nomenclature rules for coordination compounds.
Textbook Question
Four-coordinate metals can have either a tetrahedral or a square-planar geometry; both possibilities are shown here for [PtCl2(NH3)2].
a. What is the name of this molecule?
b. Would the tetrahedral molecule have a geometric isomer?
c. Would the tetrahedral molecule be diamagnetic or paramagnetic?
d. Would the square-planar molecule have a geometric isomer?
121
views
Open Question
Complete the exercises below. a. A compound with formula RuCl₃ • 5H₂O is dissolved in water, forming a solution that is approximately the same color as the solid. Immediately after forming the solution, the addition of excess AgNO₃ (aq) forms 2 mol of solid AgCl per mole of complex. Write the formula for the compound, showing which ligands are likely to be present in the coordination sphere.
Textbook Question
Which of these crystal-field splitting diagrams represents:
a. a weak-field octahedral complex of Fe³⁺ ,
b. a strong-field octahedral complex of Fe³⁺
c. a tetrahedral complex of Fe³⁺
d. a tetrahedral complex of Ni²⁺ (The diagrams do not indicate the relative magnitudes of ∆. ) [Find more in Section 23.6.]
115
views