How Many Valence Electrons Does BrF2 and BrF2+ 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.
Bromine difluoride consists of two atoms. One is a bromine atom and the other is a fluorine atom. The valence electrons of bromine difluoride are the sum of the total valence electrons of bromine and fluorine in the compound BrF2.
The bromine difluoride compound has a total of twenty-one electrons in the last orbits of bromine and fluorine. Hence, the total number of valence electrons in bromine difluoride is twenty-one.
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 BrF2, BrF2–, and BrF2+. Hopefully, after reading this article you will know more about this topic.
How to easily determine the number of valence electrons of BrF2?
The symbol form of bromine difluoride is BrF2. To determine the valence electrons of BrF2, it is first necessary to know the valence electrons of the fluorine and bromine atoms.
To determine the valence electrons of bromine difluoride we have to follow two steps. It is shown below:
Step 1: Determine the valence electrons of bromine and fluorine atoms
The atomic number of bromine is 35. So its total number of electrons is thirty-five. The electron configuration of bromine 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 bromine are seven.
On the other hand, the atomic number of fluorine is 9. So its total number of electrons is nine.
The electron configuration of fluorine shows that it has seven electrons in its last orbit. Therefore, the valence electrons of fluorine are seven.
Step 2: Determine the total number of valence electrons in the bromine difluoride compound
Bromine difluoride is a compound. It is composed of one bromine atom and two fluorine atoms.
Therefore, adding the valence electrons of one bromine atom and the valence electrons of two fluorine atoms can easily determine the valence electrons of bromine difluoride.
Mathematical Analysis:
BrF2
= 7 + (7×2)
= 21
| Bromine (Br) | Fluorine (F) | Bromine difluoride (BrF2) |
| 7 | 7 | 21 |
From the above mathematical analysis, we can see that the total number of electrons in the outermost orbit of BrF2 is twenty-one. Therefore, the valence electrons of BrF2 are twenty-one.
How to determine the valence electrons of BrF2+ and BrF2–?
The bromine difluoride compound has an unpaired electron. It is shown in the figure above. For this, bromine difluoride can accept or donate an electron.
BrF2+ will have twenty valence electrons while bromine difluoride donates one electron.
Mathematical Analysis:
BrF2+
= 7 + (7×2) – 1
= 20
On the other hand, if bromine difluoride accepts one electron, the valence electrons of BrF2– will be twenty-two.
Mathematical Analysis:
BrF2–
= 7 + (7×2) + 1
= 22
| BrF2 | BrF2+ | BrF2– |
| 21 | 20 | 22 |
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.