Govt. Exams
Entrance Exams
Zinc in brass (Cu-Zn alloy) enhances corrosion resistance through protective layer formation and improves cold-workability of copper.
Zn has lower (more negative) reduction potential than Cu, making it more easily oxidized. It acts as the anode (negative electrode) in the galvanic cell.
CO reduces Fe₂O₃ to Fe by accepting oxygen: Fe₂O₃ + 3CO → 2Fe + 3CO₂. CO is the primary reducing agent at higher temperatures.
Al₂O₃ reacts with both strong acids and strong bases, exhibiting amphoteric character. MgO is basic, Na₂O is strongly basic, and Cl₂O₇ is acidic.
Chromium has the electronic configuration [Ar]3d⁵4s¹ due to half-filled d-orbital stability, making it more stable than [Ar]3d⁴4s².
HF exhibits hydrogen bonding between H (bonded to highly electronegative F) and lone pairs on F of adjacent molecules.
Iodine has the lowest electronegativity among halogens (2.5) due to its largest atomic radius and furthest valence electrons from nucleus.
Across a period, increasing nuclear charge more significantly affects ionization energy than the slight increase in shielding, causing IE to increase.
AgCl is a white precipitate (Ksp = 1.8 × 10⁻¹⁰) formed due to the low solubility product of silver chloride.
Iron (Fe) exhibits variable oxidation states (+2 and +3) due to its incomplete d-orbitals, allowing electron transitions between different oxidation states.
