How to Find the Valence Electrons for ClO2 and ClO2-?
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. Chlorine dioxide consists of two atoms. One is a chlorine atom and the other is an oxygen atom.
The valence electrons of chlorine dioxide are the sum of the total valence electrons of chlorine and oxygen in the compound ClO2. The chlorine dioxide compound has a total of nineteen electrons in the last orbits of chlorine and oxygen.
Hence, the total number of valence electrons in chlorine dioxide is nineteen. 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 determine the valence electrons of chlorine dioxide very easily. Hopefully, after reading this article you will know more about this topic.
How to easily determine the number of valence electrons of ClO2?
The symbol form of chlorine dioxide is ClO2. To determine the valence electrons of ClO2, it is first necessary to know the valence electrons of the oxygen and chlorine atoms. To determine the valence electrons of chlorine dioxide we have to follow two steps. It is shown below:
Step 1: Determine the valence electrons of chlorine and oxygen atoms
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.
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 chlorine are seven. 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.
Step 2: Determine the total number of valence electrons in the chlorine dioxide compound
Chlorine dioxide is a compound. It is composed of one chlorine atom and two oxygen atoms. Therefore, adding the valence electrons of one chlorine atom and the valence electrons of two oxygen atoms can easily determine the valence electrons of chlorine dioxide.
Mathematical Analysis:
ClO2
= 7 + (6×2)
= 19
| Chlorine (Cl) | Oxygen (O) | Chlorine dioxide (ClO2) |
| 7 | 6 | 19 |
From the above mathematical analysis, we can see that the total number of electrons in the outermost orbit of ClO2 is nineteen. Therefore, the valence electrons of ClO2 are nineteen.
How to determine valence electrons of chlorite ion(ClO2–)?
The octet of the chlorine atom remains unfilled during chlorine dioxide bond formation. For this, chlorine dioxide can accept an electron and become a chlorite ion(ClO2–). That is, the valence electrons of chlorite ion will be twenty.
Mathematical Analysis:
ClO2–
= 7 + (6×2) + 1
= 20
| Chlorine (Cl) | Oxygen (O) | Chlorite ion (ClO2–) |
| 7 | 6 | 20 |
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 characteristic of a compound. So we need to know the valence electrons of all the elements to determine the properties of compounds.
