Question
What are borones(boron hybrides)?
Solution
(i) Boron does not directly combine with hydrogen but a number of interesting hydrides are known. Boron hydrides such as B2H6 (diborane), B4H10 (tetraborane), B5H9 (pentaborane), B6H10 (hexaborane), B10H14 (decaborane) are collectively called boranes.
(ii) Preparation of diborane:
(a) By reducing boron trifluoride with lithium hybrid. 
(b) By reducing boron trichloride with hydrogen or lithium aluminium hydride.
Uses of diborane: It is used:
(i) as fuel for supersonic rockets.
(ii) as a reducing agent in organic reactions.
(iii) for preparing LiBH4, NaBH4 etc.
