d and f BLOCK ELEMENTS Quiz

• 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

• 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

• 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

• 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

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