Hydrogen Chloride (HCl) Lewis Structure

Lewis structure of Hydrogen chloride (HCl) contains only one H-Cl bond. There are no charges on atoms in HCl lewis structure because HCl is a neutral molecule. There is three lone pairs on chlorine atom in HCl molecule.

HCl lewis structure

HCl hydrochloric acid lewis structure

There are only one hydrogen atom and one chlorine atom in HCl molecule. A hydrogen atom has made a single bond with the chlorine atom.

Steps of drawing lewis structure of HCl

When we draw a lewis structure, there are several steps to follow. Number of steps can be changed according the complexity of the molecule or ion. Because HCl molecule is a simple molecule and there is no overall charge, some of these steps are not required to use. However those all steps are mentioned and explained in detail in this tutorial.

  1. Find total number of electrons of the valance shells of hydrogen atom and chlorine atom
  2. Total electrons pairs existing as lone pairs and bonds
  3. Center atom selection
  4. Mark lone pairs on atoms
  5. Mark charges on atoms if there are charges.
  6. Check the stability and minimize charges on atoms by converting lone pairs to bonds to obtain best lewis structure.

Total number of electrons of the valance shells of HCl

There are two elements in hydrogen chloride; hydrogen and chlorine. Hydrogen is a group IA element in the periodic table and only has one electron in its last shell (valence shell). Chlorine is a group VIIA element in the periodic table and contains seven electrons in its last shell. Now, we know how many electrons are there in valence shells of hydrogen and chlorine atoms.

  • valence electrons given by hydrogen atom = 1 * 1 = 1
  • valence electrons given by chlorine atom = 7 * 1 = 7

  • Total valence electrons = 1 + 7 = 8

Total valence electrons pairs

Total valance electrons pairs = σ bonds + π bonds + lone pairs at valence shells

Total electron pairs are determined by dividing the number total valence electrons by two. For, HCl, Total pairs of electrons are four in their valence shells.

Center atom of HCl molecule

Because, there are only two elements in HCl, we do not need to worry about finding the center atom. Therefore, we can draw the skeleton of HCl.

HCl skeleton

Lone pairs on atoms

After determining the center atom and sketch of HCl molecule, we can start to mark lone pairs on atoms. Remember that, there are total of four electron pairs.

  • There is already one bond in the drawn skeleton.
  • Usually, those remaining electron pairs should be started to mark on outside atoms. However, hydrogen atom cannot keep more than two electron in its last shell. There are already two electrons in hydrogen atom. Therefore, we cannot mark those remaining electrons pairs on hydrogen atom.
  • Therefore, mark those remaining three electrons pairs on chlorine atom. Chlorine atom will take three lone pairs to fulfill the octal.
mark  lone pairs on atoms in HCl

Mark charges on atoms

There are no charges on hydrogen atom and chlorine atom. Also, remember that HCl is a molecule which does not have a charge. Therefore, not having charges on every atoms tells us we have drawn a stable structure.

Check the stability and minimize charges on atoms by converting lone pairs to bonds

Because there are no charges on atoms, no need to worry about reducing charges as a step of obtaining the best lewis structure. Therefore, we have already got the best lewis structure for HCl.


Lewis Structures of Molecules