Guest

what are banana bond and what are the reasons that boron and aluminium form this and most of the elements does not??

what are banana bond and what are the reasons that boron and aluminium form this and most of the elements does not??

Grade:12

2 Answers

Arun
25750 Points
4 years ago
Banana bond also called as Tau bond is a type of covalent bonding in chemical bonding lesson. It is also called bent bonds due its curved nature of bonding.
The bonds are represented with curved bonds but a normal bonding is represented by a sraight line(–).
The simple reason to understand why banana bonds is formed is due to some **electronic configurational density difference of an element with other element while it is in the process of bonding.**
Let us take simple example instead of organic example…
***Diborane***, a boron compound of molecular formula ***B2H6***.
* Two atoms of boron are in middle and each boron is attached with 2 atoms of hydrogen.
* So each Boron will have two atoms of hydrogen…this makes total of 4 hydrogen atoms.
* The other two hydrogen atoms is between two boron atoms.
* It is said that boron to boron direct bonding is impossible and hence an element is needed as an intermediate for bonding both boron atoms.
* Here the other two atoms of hydrogen acts as intermediate element for boron bonding.
* But when hydrogen comes between boron due to their electron density difference, the bonding becomes curved…this gives the shape of banana like figure.
* As they are two hydrogen atoms bonded to two boron atoms from both ways.. These hydrogen atoms are called as ***Bridge hydrogen.***
* The other 4 hydrogen atoms bonded are called as ***Terminal hydrogen.***
* Thus this is how Diborane exhibit banana bonds or Tau bonds. ***Diborane exhibit TWO BANANA BONDS***
 
Vikas TU
14149 Points
4 years ago
Dear student 
Four hydrogen atoms are of one type, which are used in making four normal covalent bonds with two boron atoms. The remaining two H atoms form bridges between the two boron atoms through three-centre electron-pair bonds. Since the shape of the electron cloud resembles a banana, it is called a banana bond.

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free