d and f BLOCK ELEMENTS

What is the approximate relationship between exchange energy and the number of parallel spin pairs in degenerate orbitals?

• Exchange energy is approximately proportional to the total number of possible pairs of parallel spins
• Exchange energy is inversely proportional to the number of parallel spin pairs
• Exchange energy is independent of the number of parallel spin pairs
• Exchange energy is equal to the number of parallel spin pairs

Why is the configuration d6 considered to have no loss of exchange energy?

• This statement seems incorrect; d6 configuration does have exchange energy, but perhaps refers to a specific comparison context.
• d6 configurations inherently lack unpaired electrons
• d6 configurations are always unstable
• d6 configurations have maximum exchange energy

What is the significance of the statement 'The loss of exchange energy increases the stability'?

• It explains why certain electron configurations are particularly stable
• It explains why ionization always decreases stability
• It explains why electrons always pair up
• It explains why 4s electrons are removed first

Which of the following best explains why the second ionization enthalpy is considered the dominant term for forming M2+ ions?

• It often involves removing an electron from a stable d5 or d10 configuration in the M+ ion
• It is always numerically larger than the first ionization enthalpy
• It includes the energy of atomisation
• It is easier to measure experimentally

What is the primary factor that makes the d5 configuration (like in Mn2+) resistant to further ionization?

• High exchange energy due to maximum parallel spins
• Low nuclear charge
• Large ionic radius
• Low electron affinity