Assume the N-H bonds in NH3 (H-N-H angle 107 deg) are formed by equivalent sp^n hybrid orbitals of nitrogen, for which costheta = -1/n. The percentage s-character of these orbitals is closest to

JEE Advanced levelSingle correct optionDifficulty 3 of 3cb076

Assume the N-H bonds in $NH X_{3}$ (H-N-H angle $10 7^{\circ}$ ) are formed by equivalent $s p^{n}$ hybrid orbitals of nitrogen, for which $cos θ = - 1/ n$ . The percentage s-character of these orbitals is closest to

With

cos 10 7^{\circ} = - 0.2924

n = 1/0.2924 = 3.42

. The s-character is

100/ (1 + n) = 100/4.42 = 22.6%

, a little below the 25% of ideal

s p^{3}

, as the lone pair takes more s-character.