NaF Molecular Geometry - Science Education and Tutorials

Q: What is the molecular notation for NaF molecule?

NaF molecular notation is AX1N3.

Sodium fluoride(NaF) has the composition of one fluorine and one sodium atom. What is the molecular geometry of sodium fluoride?. Drawing and predicting the NaF molecular geometry is very easy by following the given method. Here in this post, we described step by step to construct NaF molecular geometry. Fluorine and sodium come from the 17th and 1st family groups in the periodic table. Fluorine and sodium have seven and one valence electrons respectively.

Table of Contents

Key Points To Consider When drawing The NaF Molecular Geometry

A three-step approach for drawing the NaF molecular can be used. The first step is to sketch the molecular geometry of the NaF molecule, to calculate the lone pairs of the electron in the central fluorine atom; the second step is to calculate the NaF hybridization, and the third step is to give perfect notation for the NaF molecular geometry.

The NaF molecular geometry is a diagram that illustrates the number of valence electrons and bond electron pairs in the NaF molecule in a specific geometric manner. The geometry of the NaF molecule ion can then be predicted using the Valence Shell Electron Pair Repulsion Theory (VSEPR Theory) and molecular hybridization theory, which states that molecules will choose the NaF geometrical shape in which the electrons have from one another in the specific molecular structure.

Finally, you must add their bond polarities characteristics to compute the strength of the one Na-F single bonds (dipole moment properties of the NaF molecular geometry). One sodium-fluorine single bonds in the sodium fluoride(NaF), for example, are polarised toward the more electronegative value fluorine atom, and because (Na-F) single bonds have the same size and polarity, their sum is nonzero due to the NaF molecule’s bond dipole moment due to pulling the electron cloud to the two side of linear geometry, and the NaF molecule is classified as a polar molecule.

The molecule of sodium fluoride(with linear shape NaF molecular geometry) is tilted at 180 degrees bond angle of Na-F. It has a difference in electronegativity values between fluorine and sodium atoms, with fluorine’s pull the electron cloud being greater than sodium’s. But bond polarity of Na-F is not canceled to each other in the linear geometry. As a result, it has a nonzero permanent dipole moment in its molecular structure. The NaF molecule has a nonzero dipole moment due to an unequal charge distribution of negative and positive charges in the linear geometry.

Overview: NaF electron and molecular geometry

According to the VSEPR theory, the NaF molecule ion possesses linear molecular geometry. Because the center atom, fluorine, has one Na-F single bond with the one sodium atom surrounding it. The Na-F bond angle is 180 degrees in the linear NaF molecular geometry. The NaF molecule has a linear geometry shape because it contains one sodium atom in the linear and four corners with four lone pairs of electrons.

There is one Na-F single bond at the NaF molecular geometry. After linking the one sodium atom and four lone pairs of electrons on the fluorine atom (as fluoride ion) in the linear form, it maintains the linear-shaped structure. In the NaF molecular geometry, the Na-F single bond has stayed in the one terminal and four lone pairs of electrons on the fluorine atom of the linear molecule.

The center fluorine atom of NaF has four lone pairs of electrons, resulting in linear NaF electron geometry. However, the molecular geometry of NaF looks linear-shaped and has four lone pairs of electrons on the fluorine of the NaF geometry. It’s the NaF molecule’s slight asymmetrical geometry. As a result, the NaF molecule is more polar.

How to find NaF hybridization and molecular geometry

Calculating lone pairs of electrons on fluorine in the NaF geometry:

Determine the number of lone pairs of electrons in the core fluorine atom of the Lewis structure. Because the lone pairs of electrons on the fluorine atom are mostly responsible for the molecule geometry planar, we need to calculate out how many there are on the central fluorine atom of the NaF Lewis structure.

Use the formula below to find the lone pair on the fluorine atom of the NaF molecule.
L.P(F) = V.E(F) – N.A(Na-F)

Lone pair on the central fluorine atom in NaF= L.P(F)
The core central fluorine atom’s valence electron in NaF = V.E(F)
Number of Na-F bond = N.A (Na-F)
calculation for fluorine atom lone pair in NaF molecule.

For instance of NaF, the central atom, fluorine, has seven electrons in its outermost valence shell, one Na-F single bond connection. This gives a total of one connection.

As a result of this, L.P(F) = (8 –0)=8

The lone pair of electrons in the fluorine atom of the NaF molecule is four.

Calculating lone pair of electrons on sodium in the NaF geometry:

Finding lone pair of electrons for the terminal sodium atom is similar to the central fluorine atom. We use the following formula as given below

Use the formula below to find the lone pair on the sosium atom of the NaF molecule.
L.P(Na) = V.E(Na) – N.A(Na-F)

Lone pair on the terminal sodium atom in NaF = L.P(Na)
Terminal sodium atom’s valence electron in NaF= V.E(Na)
Number of Na-F bonds = N.A ( Na-F)
calculation for sodium atom lone pair in NaF molecule.

For instance of NaF, their terminal atoms, sodium, have one electron in its outermost valence shell, one Na-F single bond connection. This gives a total of one Na-F single bond connection. But we are considering only one connection for the calculation.

As a result of this, L.P(Na) = (0 –0)=0

The lone pair of electrons in the sodium atom of the NaF molecule is zero. One sodium atom is connected with the central fluorine atom.

In the NaF electron geometry structure, the lone pairs on the central fluorine atom are four, lone pairs of electrons in the sodium atom have zero. One sodium atom has no lone pairs of electrons.

It means there are four lone pairs of electrons in the core fluorine atom (as fluoride ion). Four lone pair of electrons on the central fluorine atom is responsible for the linear nature of NaF molecular geometry. But in the structure sodium atom is polarised sidewise in their linear geometry.

The four lone pairs of electrons are placed at another side of the NaF geometry. Because the sodium atom is a lower electronegative value as compared with other atoms in the NaF molecule. One sodium atom is polarized towards the sidewise in the NaF structure.

But in reality, the NaF has four lone pairs of electrons in its structure. This makes the NaF more asymmetrical in the structure of the molecule. Because there is electric repulsion between bond pairs and lone pairs.

But some sort of interaction is there between sodium empty hole and lone pairs of electrons of fluorine of another NaF molecule. Here, sodium of one molecule acts as an acceptor and fluorine of another molecule as a donor. This is called sodium bonding between the two NaF molecules. This is one of the main intermolecular forces in NaF.

But in the central, fluorine atom has four lone pairs of electrons and these lone pair electrons are placed in the four corners of the tetrahedral.

Calculate the number of molecular hybridizations of the NaF molecule

What is NaF hybridization? This is a very fundamental question in the field of molecular chemistry. All the molecules are made of atoms. In chemistry, atoms are the fundamental particles. There are four different types of orbitals in chemistry. They are named s, p, d, and f orbitals.

The entire periodic table arrangement is based on these orbital theories. Atoms in the periodic table are classified as follows:

s- block elements
p- block elements
d-block elements
f-block elements
Atoms are classified in the periodic table

NaF molecule is made of one fluorine and a sodium atom. The sodium and fluorine atoms have s and p orbitals. But sodium atom has only s orbital in the ground state. Sodium comes as the third element in the periodic table. The fluorine atom also belongs to the halogen family group. But it falls as the first element in the periodic table.

When these atoms combine to form the NaF molecule, its atomic orbitals are mixed and form unique molecular orbitals due to hybridization.

How do you find the NaF molecule’s hybridization? We must now determine the molecular hybridization number of NaF.

The formula of NaF molecular hybridization is as follows:
No. Hyb of NaF= N.A(Na-F bond) + L.P(F)
No. Hy of NaF = the number of hybridizations of NaF
Number of Na-F bonds = N.A (Na-F bonds)
Lone pair on the central fluorine atom = L.P(F)
Calculation for hybridization number for NaF molecule

In the NaF molecule, fluorine is a core central atom with one sodium atom connected to it. It has four lone pairs of electrons on fluorine (as a fluoride ion). The number of NaF hybridizations (No. Hyb of NaF) can then be estimated using the formula below.

No. Hyb of NaF= 4+0=4

The NaF molecule ion hybridization is four. The fluorine and sodium atoms have s and p orbitals. The sp3 hybridization of the NaF molecule is formed when one s orbital and three p orbitals join together to form the NaF molecular orbital.

Molecular Geometry Notation for NaF Molecule :

Determine the form of NaF molecular geometry using VSEPR theory. The AXN technique is commonly used when the VSEPR theory is used to calculate the shape of the NaF molecule.

The AXN notation of NaF molecule is as follows:
The central fluorine atom in the Na molecule is denoted by the letter A.
The bound pairs (one Na-F bonds) of electrons to the core fluorine atom are represented by X.
The lone pairs of electrons on the central fluorine atom are denoted by the letter N.
Notation for NaF molecular geometry

We know that fluorine is the core atom, with no electron pair bound (one ionic bond Na-F) and four lone pairs of electrons. The general molecular geometry formula for NaF is AN4.

According to the VSEPR theory, if the NaF molecule ion has an AN4 generic formula, the molecular geometry and electron geometry will both be linear-shaped forms.

Name of Molecule	Sodium fluoride
Chemical molecular formula	NaF
Molecular geometry of NaF	linear
Electron geometry of NaF	linear
Hybridization of NaF	sp3
Bond angle (Na-F)	180º degree
Total Valence electron for NaF	8
The formal charge of NaF on fluorine	0

Summary:

In this post, we discussed the method to construct NaF molecular geometry, the method to find the lone pairs of electrons in the central NaF atom, NaF hybridization, and NaF molecular notation. Need to remember that, if you follow the above-said method, you can construct the NaF molecular structure very easily.