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Lewis Structure of SCl2 and Hybridization of SCl2

The Lewis Structure of SCl2, sulfur dichloride, has a sulfur atom (which brings six valance electrons) bonded two chlorine atoms (which each bring seven valence electrons). By drawing the Lewis Structure accurately, we can determine the shape and hybridization of SCl2 as well.

Since chlorine needs to share just one extra electron to complete its octet, the sulfur is able to share each of its two unpaired electrons to form bonding pairs with chlorine.

Sulfur and Chlorine are both non-metals, which makes these bonds covalent. We can determine the type of covalent bond with a calculation of electronegativity difference: ΔEN = 3.16 – 2.58 = 0.58, which makes the bond polar covalent.

Substances with similar chemical formulas, such as CaBr2, are ionic and so their Lewis Structures are drawn very differently.

The lewis structure is shown here:

The Lewis Structure of SCl2, sulfur dichloride, has one sulfur single-bonded two each of two chlorine atoms.

The sulfur atom here has two bonding pairs (shown as horizontal lines) and two lone pairs (shown as two dots for each pair). None of these require pi-bonding (which is the method of formation for double and triple bonds). Thus, the hybridization of SCl2 is sp3.

In addition, because there are two bonding pairs and two lone pairs, we can say that the VSEPR notation is AX2E2 and the molecular shape is angular/bent. Indeed, the bond angle is significantly less than it would be in tetrahedral, since the lone pairs take up more space than bonding pairs. The bond angle in SCl2 is 103 degrees (Source).

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Lewis Structure of Calcium Bromide (CaBr2) Step-by-Step

Calcium is a metal, in fact it is an alkaline earth metal in Group 2 of the periodic table. Bromine is a halogen in Group 17 and all of the halogens are non-metals.

When metals and non-metals react together, they form ionic compounds. This means that electrons are transferred from one atom to another, which creates positively-charged ions (cations) and negatively-charged ions (anions).

So how is calcium bromide (CaBr2) formed?

Since calcium has two valence electrons, and bromine has seven (which is one short of a full octet), ONE calcium atom will give away ONE electron to each of two bromine atoms. I use single-headed arrows to show that here:

This leaves you with a calcium atom that has lost two electrons and therefore has a +2 charge. I know it’s weird that losing something causes it to become plus-charged, but electrons are negative so it’s like you’re subtracting negatives.

The bromine atoms on the other hand gained one electron each, and therefore they now each have a -1 charge.

These charged particles are shown with their new numbers of valence electrons (zero for calcium, eight for each bromine) and are put in square brackets with the charge written in the top right corner:

Some teachers will allow you to show the two bromine ions this way:

But confirm that with your teacher first.

Want to watch me explain it instead? Here you go: