P-Block Elements Ques 378
Question: In compounds of type $ ECl_3 $ , where $ E=B, $ P, As or $ Bi $ , the angles $ Cl-E-Cl $ for different E are in the order
[IIT-JEE 1999]
Options:
A) $ B>P=As=Bi $
B) $ B>P>As>Bi $
C) $ B<P=As=Bi $
D) $ B<P<As<Bi $
Show Answer
Answer:
Correct Answer: B
Solution:
$BCl_3$ is trigonal planar in structure and bond angles are 120o each. $PCl_3,AsCl_3, and BiCl_3$ are pyramidal in shape with $sp^3$-hybridization.In all of them, the bond angles are less than the normal tetrahedral angle of 109.28’, and also these bond angles decrease down the group.Therefore, the correct order of bond angles is as follows:
$ B>P>As>Bi $
