Discussion Forum



1)

THe crystalline form of borax has 


A) tetranuclear $[B_{4}O_{5}(OH)_{4}]^{2-}$ unit

B) all boron atoms in the same plane

C) equal number of $sp^{2}$ and $sp^{3}$ hybridised boron atoms.

D) one terminal hydroxide group atom

Answer:

Option A,C.D

Explanation:

$Na_{2}B_{4}O_{7}.10H_{2}O$  (borax) is actually made of two tetrahedral and two triangular units and is actually written as 

 $Na_{2}[B_{4}O_{5}(OH)_{4}].5H_{2}O$ 

1822021565_C22.JPG

(a)  Thus, correct

(b) Boron atoms are in different planes thus, incorrect

(c) Two  $sp^{2}$ and two  $sp^{3}$ - hybridised B atoms thus, correct

 (d) Each boron has one- OH group thus, correct