Which of these pairs of molecules have similar shapes?

A. #AlCl_3# and #BCl_3#
B. #AlCl_3# and #PCl_3#
C. #BCl_3# and #NH_3#
D. #BeCl_2# and #H_2O#

1 Answer
Jan 24, 2018

A.

Explanation:

Both Al & B have only 3 valance electrons so will have an the same electron domain of trigonal planar. The 3 electrons are bonded, no unbonded electrons on the central atom.
B, there is a pair of unbonded electrons on the central P atom.
C, same as B, but central atom is N.
D, Be only has 2 valance electrons & water has a central atom of O that has 2 pair unbonded electrons