Govt. Exams
Entrance Exams
Co²⁺ is d⁷. Water is a weak field ligand with small Δ, resulting in high spin configuration (t₂g⁵ eg²) with 4 unpaired electrons.
Fe²⁺ has 4 unpaired electrons (d⁶ configuration). Magnetic moment = √[n(n+2)] = √[4×6] = 4.90 BM
Positive E° means Fe³⁺ is easily reduced and Fe²⁺ is easily oxidized. Fe³⁺ is a strong oxidizing agent relative to Fe²⁺.
Borax is a complex borate with formula Na₂B₄O₅(OH)₄·8H₂O, containing both triangular BO₃ and tetrahedral BO₄ units.
Fe₀.₉₅O is a non-stoichiometric compound with variable composition. It contains both Fe²⁺ and Fe³⁺ ions due to defects in crystal structure.
Blister copper (impure copper from smelting) acts as the anode. Pure copper is the cathode. Impurities fall as anode mud.
CN⁻ is a strong field ligand causing pairing in d-orbitals. Fe²⁺ becomes diamagnetic with μ = 0 B.M. (t₂g⁶eg⁰ configuration).
H₂O₂ disproportionates: H₂O₂ → H₂O + ½O₂. NaClO: 3ClO⁻ → 2Cl⁻ + ClO₃⁻. Both show disproportionation.
SF₆ has 6 bonding pairs and 0 lone pairs on S. Coordination number = 6, requiring sp³d² hybridization with octahedral geometry.
BCl₃ forms a dimer (B₂Cl₆) in gaseous state due to bridging chlorine atoms. BF₃ remains monomeric due to strong B-F bonds and p-p repulsion.