Plzz explain the structure of diborane nd boric acid..plzz give it frnds..love u..
Answers
structure of diborane :- In diborane, the four terminal Hydrogen atoms and two boron atoms lies on in one plane. Above and below this plane, there are two bridging Hydrogen atoms .The four terminal B - H bonds are regular bonds while two bridge bonds ( B - H - B) are different and known as banana bonds (3-centre - 2- electrons bridge bonds )
structure of boric acid :- Boric acid has a layer structure in which H3BO3 units are joined by Hydrogen bonds .The adjacent layers in the cystal of boric acid are held together by week forces of attraction. the distance between any two successive layer is 318 pm . because of weak forces of attraction , one layer can slide over other . this make boric acid soft and soapy to touch.
Diborane B2H6 is an electron-deficient compound. B2H6 has only 12 electrons - 6 e- from 6 H atoms and 3 e-each from 2 B atoms. Thus, after combining with 3 H atoms, none of the boron atoms has any electrons left. X-ray diffraction studies have shown the structure of diborane as:
2 boron and 4 terminal hydrogen atoms (Ht) lie in one plane, while the other two bridging hydrogen atoms (Hb) lie in a plane perpendicular to the plane of boron atoms. Again, of the two bridging hydrogen atoms, one H atom lies above the plane and the other lies below the plane. The terminal bonds are regular two-centre two-electron (2c - 2e-) bonds, while the two bridging (B-H-B) bonds are three-centre two-electron (3c - 2e-) bonds.
(b) Boric acid Boric acid has a layered structure. Each planar BO3 unit is linked to one another through H atoms. The H atoms form a covalent bond with a BO3 unit, while a hydrogen bond is formed with another BO3 unit. In the given figure, the dotted lines represent hydrogen bonds.
