# Draw the Lewis electron dot structure for SF_2. How many lone pairs of electrons are on the central atom?

Mar 6, 2017

$\text{There are 2 lone pairs on the central sulfur............}$
We have $2 \times 7 + 6$ $\text{valence electrons}$ to distribute.........each chlorine atom claims 7, and the sulfur atom claims 6.
Given that the central sulfur has 4 electron pairs surrounding it, 2 bonding, and 2 non-bonding, VESPER predicts that these are arranged in a tetrahedron to a first approx. The $\angle F - S - F$ $< {109.5}^{\circ}$ given the sulfur lone-pairs compress the $\angle F - S - F$ bond angle.
This site reports that $\angle F - S - F = {98.3}^{\circ}$ which is compressed indeed (more so than in $O {F}_{2}$, where the corresponding $\angle F - O - F = {103}^{\circ}$, an angle for which VESPER could account). Ask your inorganic prof to account for this compressed bond angle. If he (or she) answers you, post the account here.