Inorganic Chemistry

• All B atoms are sp³ hybridised: Each boron atom in B₂H₆ is bonded to four other atoms (two terminal H atoms and two bridging H atoms). To accommodate these four bonds, the boron atoms undergo sp³ hybridization. Therefore, this statement is correct.
• It is paramagnetic: B₂H₆ is diamagnetic because all of its electrons are paired. The molecule does not have any unpaired electrons. Therefore, this statement is incorrect.
• It contains 3C - 4e bonding: B₂H₆ contains two 3-center-2-electron (3c-2e) bonds, *not* 3C-4e. Each bridge consists of a boron atom, a hydrogen atom, and another boron atom, sharing two electrons across these three atoms. Therefore, this statement is incorrect.
• There are two types of H present: B₂H₆ has two types of hydrogen atoms: terminal hydrogen atoms and bridging hydrogen atoms. The four terminal hydrogen atoms are bonded directly to a single boron atom via normal 2-center-2-electron bonds. The two bridging hydrogen atoms are each involved in a 3-center-2-electron bond. Therefore, this statement is correct.

Correct Answer: All B atoms are sp³ hybridised, There are two types of H present.