Topic 1 - The shape of activated complex

What is the most fundamental reaction a complex can undergo?

• Ligand dissociation

• Ligand substitution

• Ligand coordination

• Ligand formation

What term is used for complexes that react quickly?

• Nonlabile

• Labile

• Stable

• Inert

Which of the following complexes is an example of a nonlabile complex? (a)  

• [Ni(NH3)6]2+
• [CoCl(OH2)5]2+
• [Co(NH3)5(OH2)]3+
• [Ni(OH2)6]2+

What is the classification of a reaction mechanism that involves the formation of an intermediate with a higher coordination number?

• Associative

• Interchange

• Dissociative

• Sequential

Which mechanism is characterized by the exchange of leaving and entering groups in a single step?

• Sequential

• Interchange

• Associative

• Dissociative

What is the term for the rate-determining step that is largely independent of the identity of the entering group?

• Sequential

• Interchange

• Dissociative

• Associative

Which of the following factors affects the rates of ligand substitution reactions? (a)  

• Concentration of solvent
• Color of the complex
• Temperature
• Identity of the incoming ligand

Match the following effects with their corresponding names.

• Effect of a ligand trans to the leaving group on substitution rate

• Cis effect

• Effect of a ligand cis to the leaving group

• Trans influence

• Effect due to spatial arrangement of atoms

• Steric hindrance

• Effect related to the coordination of ligands

• Coordination effect

Which of the following ligands is considered a strong π-acceptor?

• CO

• Br-

• NH3

• Cl-

What is the nucleophilicity parameter used to express?

• The strength of the leaving group

• The reactivity of the entering group

• The coordination number

• The stability of the complex