`{:(,"Column - I",,"Column - II"),((A),B_(2)H_(6)+NH_(3)overset(" under different ")underset(" temperatures ")rarr,(P),B_(2)H_(6)),((B),2BF_(3)+6LiH rarr,(Q),"Borazine"),((C ),"Two electron four centre bond",(R ),AlCl_(3) ("vapour")),((D),sp^(3)" hybrid orbitals",(S),"Inorganic graphite"):}`

Answer

A-QS, B-P, C-P, D-PR

Explanation

(A) `B_(2)H_(6)+6NH_(3)overset(450 K)underset(-12 H_(2))rarr underset("Inorganic benzene")underset("Borazine (or)")(2B_(3)N_(3)H_(6))overset(Delta)rarr underset("Inorganic graphite")((BN)_(X))`
(B) `2BF_(3)+6LiH overset(450 K)rarr underset("Diborane")(B_(2)H_(6))+6LiF`
(C ) Two electron three centre bond `to B_(2)H_(6)`
(D) `sp^(3)` hybrid orbit also `to B_(2)H_(6), AlCl_(3)` (vapour).