How do you determine the molecular geometry of the molecule #BeCl_2#?

1 Answer
Aug 17, 2017

Apply, VESPER.......and we get a linear #BeCl_2# molecule.

Explanation:

How many valence electron pairs surround the central beryllium atom? Beryllium forms 2 electron pairs to make #2xxBe-Cl# bonds. VESPER suggests that the electron pairs are arranged in a way that MINIMIZES their interaction, and thus #/_Cl-Be-Cl=180^@#; the molecule is therefore LINEAR.

Around each chlorine atom there are 4 electron pairs (the 7 native Cl electrons), and the one from beryllium involved in the #Be-Cl# bond. These electron pairs are arranged in a tetrahedral geometry, but because these are non-bonding lone pairs, here they do not influence geometry.