Chemistry

Chemistry

Problem

If the central atom is of third row or below this in the periodic table, then lone pair will occupy a stereochemically inactive ss -orbital and bonding will be through almost pure pp -orbitals and bond angles are nearly 90∘90^\circ , if the substituent's electronegativity value is ≤2.5\le 2.5 . In which of the following option, covalent bond is having maximum s%s\% character? a. S — H bond in H2SH_2S b. P — H bond in PH3PH_3 c. N — H bond in NH3NH_3 d. All have equal s%s\% character
Intuitive explanation

The key insight is that ss-character in a bond depends on the hybridization of the orbitals forming it—higher ss-character means more spsp mixing and closer to linear geometry. For atoms in the third row and below with electronegativity ≤2.5\le 2.5, lone pairs sit in pure ss-orbitals while bonding uses nearly pure pp-orbitals (giving 90° angles and minimal ss-character). To maximize ss-character, you need either lower hybridization (like spsp for 180° bonds) or atoms where this "pure pp-bonding" rule doesn't apply—typically second-row elements or higher electronegativity substituents that force more ss-orbital involvement.

Intuitive explanation

The key insight is that ss-character in a bond depends on the hybridization of the orbitals forming it—higher ss-character means more spsp mixing and closer to linear geometry. For atoms in the third row and below with electronegativity ≤2.5\le 2.5, lone pairs sit in pure ss-orbitals while bonding uses nearly pure pp-orbitals (giving 90° angles and minimal ss-character). To maximize ss-character, you need either lower hybridization (like spsp for 180° bonds) or atoms where this "pure pp-bonding" rule doesn't apply—typically second-row elements or higher electronegativity substituents that force more ss-orbital involvement.

Browse the problem library