We use molecular orbital theory to calculate the bond order between two atoms. It’s very interesting to draw the energy level diagram of the atoms. Read more What is the Bond Order in F2?
Answer- 1 is the bond order for an f2 molecule. We calculate the bond order with the help of molecular orbital theory or bond order theory. The theory and the explanation of how the f2 molecule has 1 as its bond order, which is detailed in the next sections of the article.
Before jumping to calculations and other technical things first, we should know the basics of this topic.
What is a bond order?
Bond order is the number of possible bonds between two atoms. As the bond order of diatomic nitrogen is 3 i.e. two nitrogen atoms are connected with a triple bond (N≡N).
The bond order signifies the strength of the bonding between atoms. The bond is stronger when the bond order is high and vice versa.
The bond order also tells about the length of the bond between atoms. The bond length and bond order are inversely proportional to each other.
This means if any molecule has high bond order then its bond length is short and vice versa.
We can also find the magnetic properties of an atom from its bond order. If there are two electrons in the molecular orbitals of an atom, then it’s diamagnetic. However, if there’s a single electron in one or two molecular orbitals of the atom, then it is paramagnetic.
The formula to know the bond order is Nb−Na/2.
Here, Nb represents the number of bonding orbitals.
Na represents the number of antibonding orbitals.
Before discussing the bond order first, let’s know about the properties of fluorine.
Fluorine is the ninth element in the atomic table. This means its atomic number is 9, and it has nine electrons. Normally it’s present in gas form. It has a pale yellow-green color. It is a halogen and forms salt when reacted with metals.
Bond order of the f2 molecule using molecular orbital theory.
If we draw the bond structure of the f2 molecule and distribute the bonding and antibonding electrons using the molecular orbital theory, then we can calculate the bond order of the molecule. In the case of a fluorine molecule has a total of 18 electrons and out of which 14 electrons are valence electrons.
When we make the molecular orbital energy level diagram of f2 molecule then, we will get this configuration: 1σs2, 1σ*s2, 2σs2, 2σ*2, σ2pz2, π2px2, π2py2, πpx*2, π2py*2. From this electronic configuration, we can see that there are a total of ten bonding molecular orbitals and eight antibonding molecular orbitals.
Here, Na=10, Nb=8 now put it into the formula of bond order.
So, according to the formula of bond order: B.O. = Na-Nb/2
= 1 which implies that f2 is combined with a single bond.
The magnetic property of f2
We can contemplate from the molecular orbital energy level distribution of f2 energy orbitals that there’s no unpaired electron in an orbital so, the f2 molecule is diamagnetic.
You might wonder what diamagnetism means. So diamagnetism is the property of the atom or molecule not to react when the magnetic field is passed through it.
And paramagnetism is the property of an atom or molecule to react when the magnetic field is passed through it. If there are unpaired electrons in the outermost shell of the atom, then it will react as a paramagnetic atom.
Oxygen shows paramagnetism.
Molecular orbital theory
This theory was proposed by F. Hund and R.S. Milliken in 1932. According to this theory electrons of an atom are present in different atomic orbitals. These atomic orbitals of the same energy level combine and make molecular orbitals together.
Bonding and antibonding orbitals?
Two molecular orbitals are formed after the combination of two atomic orbitals. Of these two molecular orbitals, one is a bonding molecular orbital and the other is an antibonding molecular orbital.
The energy of the bonding molecular orbital is lower, and hence it has greater stability and vice versa in the case of the anti-bonding molecular orbital (i.e., it is less stable).
The molecular orbital theory helps in calculating the bond order of an atom. We have shown the distribution of energy levels in a fluorine molecule using the molecular orbital theory. The bond order of any molecule/atom helps us in identifying different properties of that atom including, its magnetic nature, number of bonds, the strength of the bonding, and length of the bond.
A similar method can be used to find all this information about any other molecule, including O2, N2, H2, Li2, etc.
Frequently Asked Questions (FAQs)
Q.1: How is an f2 molecule bonded?
The f2 molecule shares a pure covalent bonding.
Q.2 what is the bond order of O2?
2 is the bond order of O2.
Q.3: Which is a stronger bond, NO or N2?
N2, since N2 has a greater bond order (3) than NO (2.5) and hence, bonding in the N2 molecule will be stronger.
Q.4 what are the bond order and magnetic property of the f2 molecule?
F2 has a bond order of 1, and it is diamagnetism.