Question

Predict the molecular structure (including bond angles) for each of the following.

Answer 1

Answer:

PCl3 - trigonal pyramidal <109 degrees

SCl2 - bent<109 degrees

SiF4 - tetrahedral 109 degrees

Explanation:

The shape of all three molecules derive from a tetrahedral arrangement of electron pairs.

However, in PCl3 there is a lone pair of electrons on P and three bond pairs. This leads to the observance of a trigonal pyramidal geometry with bond angle <109 degrees.

In SCl2, there are four regions of electron density around S, two lone pairs and two bond pairs leading to a bent molecular geometry with bond angle <109 degrees.

In SiF4, there are four bond pairs and no lone pair. The molecular geometry is tetrahedral with a bond angle of 109 degrees.