Question

In the given structure of Diborane, \( \theta_1, \theta_2 \) are respectively:

• A. \( 101^\circ, 118^\circ \)
• B. \( 118^\circ, 101^\circ \)
• C. \( 97^\circ, 120^\circ \)
• D. \( 120^\circ, 97^\circ \)

Hint:

Diborane has unusual three-center two-electron bonds, which lead to different bond angles. Remember: - Bridge hydrogen bond angle \( \theta_1 = 97^\circ \). - Terminal hydrogen bond angle \( \theta_2 = 120^\circ \).

Answer 1

The Correct Option is C

Step 1: Understanding Diborane Structure Diborane (\( B_2H_6 \)) consists of two boron atoms bonded to four terminal hydrogen atoms and two bridging hydrogen atoms. The structure includes two types of bond angles: - The bridge hydrogen atoms form a bond angle (\( \theta_1 \)) of \( 97^\circ \). - The terminal hydrogen atoms form a bond angle (\( \theta_2 \)) of \( 120^\circ \). This occurs due to the presence of three-center two-electron bonds in the bridging hydrogens, causing bond angle distortions.