Govt. Exams
Entrance Exams
Zinc has a coordination number of 4 in this complex as four cyanide ligands are bonded to it. This follows the typical tetrahedral geometry for Zn²⁺.
In the thermite reaction (2Al + Fe₂O₃ → Al₂O₃ + 2Fe), aluminum is oxidized from 0 to +3 oxidation state as it reduces Fe₂O₃.
In KMnO₄, K is +1, O is -2, so Mn is +7. This makes permanganate a strong oxidizing agent.
PCl₃ has trigonal pyramidal geometry with one lone pair on phosphorus. Bond angle is approximately 107° due to lone pair repulsion.
SF₆ has 6 bonding pairs around sulfur with no lone pairs, requiring sp³d² hybridization for octahedral geometry.
Copper has atomic number 29 with configuration [Ar]3d¹⁰4s¹. It exhibits anomalous behavior by having a completely filled d-orbital.
Cu²⁺ is surrounded by 4 water molecules in the coordination sphere and 2 more from the sulfate ion or additional water molecules, giving octahedral geometry with coordination number 6.
Noble gases have VERY HIGH ionization energies (not low) due to their stable electron configuration. All other options are correct properties of noble gases.
N₂O₄ is colorless gas, not blue. NO is colorless, NO₂ is brown/reddish-brown, and N₂O is indeed called laughing gas.
Fluorine has the highest electronegativity value (4.0 on Pauling scale) among all elements due to its small size and high nuclear charge.
