How Many Valence Electrons Does COCl2 (phosgene) Have?

The total number of electrons in the last orbit of an element is called the valence electrons of that element.

Two or more elements combine to form compounds. The valence electrons of a compound are the sum of the total valence electrons of each element in that compound.

Phosgene is composed of three elements. One is carbon, and the other two elements are oxygen and chlorine. The valence electrons of phosgene are the sum of the total valence electrons of carbon, oxygen, and chlorine in the compound COCl₂.

The phosgene compound has twenty-four electrons in the last orbits of carbon, oxygen, and chlorine. Hence, the total number of valence electrons in phosgene is twenty-four.

To determine the valence electrons of a compound, the number of valence electrons in each element of the compound must be known.

This article discusses in detail how to easily determine the valence electrons of phosgene. Hopefully, after reading this article you will know more about this topic.

Try the Valence Electrons Calculator and get instant results for any element.

How to easily determine the number of valence electrons of COCl₂?

The symbol form of phosgene is COCl₂. To determine the valence electrons of COCl₂, it is first necessary to know the valence electrons of the carbon, oxygen, and chlorine atoms.

To determine the valence electrons of phosgene we have to follow two steps. It is shown below:

Step 1: Determine the valence electrons of carbon, oxygen, and chlorine atoms

The atomic number of carbon is 6. So its total number of electrons is six. The electron configuration of carbon shows that it has four electrons in its last orbit.

We already know that the electrons in the last orbit of an element are the valence electrons of that element. Therefore, the valence electrons of carbon are four.

On the other hand, the atomic number of oxygen is 8. So its total number of electrons is eight.

The electron configuration of oxygen shows that it has six electrons in its last orbit. Therefore, the valence electrons of oxygen are six. Again, the atomic number of chlorine is 17. So its total number of electrons is seventeen.

The electron configuration of chlorine shows that it has seven electrons in its last orbit. Therefore, the valence electrons of chlorine are seven.

Step 2: Determine the total number of valence electrons in the phosgene compound

Phosgene is a compound. It is composed of one carbon atom, one oxygen atom, and two chlorine atoms. Therefore, adding the valence electrons of one carbon atom, one oxygen atom and two chlorine atoms can easily determine the valence electrons of phosgene.

Mathematical Analysis:

COCl₂

= 4 + 6 + (7×2)

= 24

From the above mathematical analysis, we can see that the total number of electrons in the outermost orbit of phosgene is twenty-four. Therefore, the valence electrons of phosgene are twenty-four.

Why do you need to know the valence electrons of an element?

In addition to knowing the number of electrons of an element, it is also necessary to know the number of valence electrons of that element. The number of valence electrons of an element carries important properties of that element.

Many important properties of elements and compounds can be determined by valence electrons. Some important features are mentioned below:

• Determining the element’s position in the periodic table
• Determining the number of groups of elements in the periodic table
• Determining Valency
• Lewis dot formation
• Determination of the molecular structure of the compound
• Determination of bond pairs and non-pair electrons of compounds

Valence electrons are related to the characteristics of a compound. So we need to know the valence electrons of all the elements to determine the properties of compounds.