H2S Lewis structure

H₂S (hydrogen sulfide) has two hydrogen atoms and one sulfur atom.

In the H₂S Lewis structure, there are two single bonds around the sulfur atom, with two hydrogen atoms attached to it, and on the sulfur atom, there are two lone pairs.

Alternative method: Lewis structure of H₂S

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, hydrogen lies in group 1, and sulfur lies in group 16.

Hence, hydrogen has one valence electron and sulfur has six valence electrons.

Since H₂S has two hydrogen atoms and one sulfur atom, so…

Valence electrons of two hydrogen atoms = 1 × 2 = 2
Valence electrons of one sulfur atom = 6 × 1 = 6

And the total valence electrons = 2 + 6 = 8

Learn how to find: Hydrogen valence electrons and Sulfur valence electrons

• Second, find the total electron pairs

We have a total of 8 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 8 ÷ 2 = 4

• Third, determine the central atom

Here hydrogen can not be the central atom. Because the central atom is bonded with at least two other atoms, and hydrogen has only one electron in its last shell, so it can not make more than one bond.

Hence, here we have to assume that the central atom is sulfur.

Therefore, place sulfur in the center and hydrogens on either side.

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 4 electron pairs. And two S — H bonds are already marked. So we have to only mark the remaining two electron pairs as lone pairs on the sketch.

Also remember that sulfur is a period 3 element, so it can keep more than 8 electrons in its last shell. And hydrogen is a period 1 element, so it can not keep more than 2 electrons in its last shell.

Always start to mark the lone pairs from outside atoms. Here, the outside atoms are hydrogens. But no need to mark on hydrogen, because each hydrogen has already two electrons.

So for sulfur, there are two lone pairs.

Mark the lone pairs on the sketch as follows:

Formal charge

Use the following formula to calculate the formal charges on atoms:

Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons

For each hydrogen atom, formal charge = 1 – 0 – ½ (2) = 0

For sulfur atom, formal charge = 6 – 4 – ½ (4) = 0

Here, both sulfur and hydrogen atoms do not have charges, so no need to mark the charges.

Final structure

The final structure of H₂S features a central sulfur atom connected to two hydrogen atoms through single covalent bonds. In this arrangement, the sulfur atom satisfies the octet rule by maintaining two lone pairs alongside its two bonding pairs. Each hydrogen atom reaches its stable duet state through its single shared bond. This configuration is the most stable because it results in formal charges of zero for all atoms involved, representing the most energetically favorable state for the molecule. Accordingly, this specific electronic distribution serves as the definitive and most accurate Lewis representation of hydrogen sulfide.

Next: OF₂ Lewis structure

External video

• H2S Lewis Structure – How to Draw the Dot Structure for H2S – YouTube • Wayne Breslyn

External links

• https://geometryofmolecules.com/h2s-lewis-structure-molecular-geometry-hybridization-polarity/
• https://whatsinsight.org/h2s-lewis-structure/
• https://www.chemistryscl.com/general/H2S-lewis-structure/index.php
• https://techiescientist.com/h2s-lewis-structure/
• https://www.thegeoexchange.org/chemistry/bonding/Lewis-Structures/H2S-Lewis-structure.html
• https://topblogtenz.com/h2s-molecular-electron-geometry-sh2-lewis-dot-structure-bond-angle/
• https://lambdageeks.com/h2s-lewis-structure/
• https://www.makethebrainhappy.com/2020/03/lewis-dot-structure-for-h2s.html