How Many Valence Electrons Does Formaldehyde Have (CH2O)?
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.
Formaldehyde is composed of three elements. One is carbon, and the other two elements are hydrogen and oxygen. The valence electrons of formaldehyde are the sum of the total valence electrons of carbon, hydrogen, and oxygen in the compound CH2O.
The formaldehyde compound has a total of twelve electrons in the last orbits of carbon, hydrogen, and oxygen. Hence, the total number of valence electrons in formaldehyde is twelve.
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 formaldehyde. Hopefully, after reading this article you will know more about this topic.
How to easily determine the number of valence electrons of CH2O?
The symbol form of formaldehyde is CH2O. To determine the valence electrons of CH2O, it is first necessary to know the valence electrons of the carbon, hydrogen, and oxygen atoms.
To determine the valence electrons of formaldehyde we have to follow two steps. It is shown below:
Step 1: Determine the valence electrons of carbon, hydrogen, and oxygen 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 hydrogen is 1. So its total number of electrons is one.
The electron configuration of hydrogen shows that it has an electron in its last orbit. Therefore, the valence electrons of hydrogen are one. Again, 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.
Step 2: Determine the total number of valence electrons in the formaldehyde compound
Formaldehyde is a compound. It is composed of one carbon atom, two hydrogen atoms, and one oxygen atom.
Therefore, adding the valence electrons of one carbon atom, two hydrogen atoms, and one oxygen atom can easily determine the valence electrons of formaldehyde.
Mathematical Analysis:
CH2O
= 4 + (1×2) + 6
= 12
| Carbon (C) | Hydrogen (H) | Oxygen (O) | Formaldehyde (CH2O) |
| 4 | 1 | 6 | 12 |
From the above mathematical analysis, we can see that the total number of electrons in the outermost orbit of CH2O is twelve. Therefore, the valence electrons of CH2O are twelve.
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.