Polar or nonpolar is SF4?

SF4 is the formula for the chemical compound sulphur tetrafluoride. This chemical compound is a colourless gas. It is also one of the most effective organic fluorinating agents. Many of you may question whether or not SF4 is polar or nonpolar. This essay will investigate the solution to this question as well as its qualities and applications.

Consequently, is SF4 Polar or Nonpolar? SF4 (Sulfur tetrafluoride) is polar due to the presence of a lone pair on the sulphur atom, which causes the molecule to have an asymmetric, seesaw-like structure. In addition, because Fluorine is more electronegative than Sulfur, the overall charge distribution of a molecule is uneven, resulting in a polar molecule with a dipole moment of 0.632 D.

Sulfur tetrafluoride is a chemical compound also known as Sulfur(IV) fluoride according to its IUPAC nomenclature.

This chemical is one of the most effective fluorinating agents due to its high fluorine content.

SF4 has a molecular mass of 108.07 g/mol. Considered as follows:

Molar weight of SF4 = 1 * (32) Molar mass of S plus 4* (18.9) F has a mol mass of 108.07 g/mol.

In terms of its chemical composition, sulphur tetrafluoride contains one sulphur atom and four fluorine atoms.

The sulphur atom has six valence electrons, of which four contribute in the formation of sigma bonds with four fluorine atoms and two form a lone pair.

Fluorine has seven valence electrons and requires one more to complete its octet; it shares one electron with sulphur, leaving sulphur with one lone pair.

Consequently, there is electrical repulsion between the lone pair and bond pair, and the resulting molecule has a seesaw shape.

SF4 molecules have an unequal distribution of charges due to their asymetric molecular geometry.

In addition, the electronegativity of fluorine and sulphur differs, with sulfur’s electronegativity being 2.58 and fluorine’s being 3.98.

Fluorine, being more electronegative, attracts the bound electron pair with more effect and acquires a partial negative charge, whereas the other atom acquires a partial positive charge.


Polar and Nonpolar Molecular Structures

There are various types of forces that bind the molecules together. This includes ionic bonding, covalent bonding, metallic bonding, and hydrogen bonding.

Covalently bound molecules can be either polar or nonpolar. Let’s analyse the distinctions between polar and nonpolar molecules.

Polar Molecules: These molecules lack a homogeneous charge distribution across their atoms. These compounds’ dipole moments are always greater than zero.

Due to the differential electronegativity of the atoms in these molecules, the atoms exert unequal impact on the linked electron pair.

When two atoms with different electronegativity values create a covalent bond, the resulting bond tends to be polar.

Typically, the geometry of polar molecules is observed to be asymetrical.

H2O and SO2 are two examples of these molecules. You can investigate the explanation behind SO2’s polarity.

Nonpolar Molecules: Molecules with a homogeneous charge distribution among their atoms are referred to as nonpolar molecules.

The electronegativity of two atoms that form a nonpolar covalent bond is equal, thus both atoms will share an electron pair equally.

In general, the geometry of nonpolar molecules is observed to be symmetrical.

Examples of such compounds include XeF2 and O2. You can investigate the cause of XeF2’s non-polarity.

How come SF4 Polar?

As noted above, the geometry of a molecule is a significant indicator of its polarity.

Checking the VSEPR diagram reveals that the sulphur atom has one lone pair, causing the form of SF4 to be asymmetric, or seesaw-like.

Fluorine is more electronegative than sulphur, meaning it attracts the bound electron pair slightly more strongly to itself and acquires a partial negative charge, whereas sulphur acquires a partial positive charge.

Thus, the charge distribution on the atoms of the SF4 molecule becomes uneven.

The fluorine side becomes the negative pole, while the sulphur atom in the centre becomes the positive pole.

SF4’s dipole moment has a value of 0.6322 D.

Checkpoints Polarity of a compound

Electronegativity: the electronegativity of an atom refers to its ability to attract a pair of bound electrons. The greater an atom’s electronegativity, the more it pulls electrons to its side.

If there is a discrepancy between the electronegativity of two atoms that make up a molecule, the resulting molecule will be polar because its atoms will have different amounts of charge.

Consequently, the polarity of a molecule is proportional to the difference in their electronegativity, and vice versa.

In the case of symmetric geometry, however, molecules with unequal electronegativity can also be nonpolar, as the dipoles are cancelled out by one another.

The geometrical shape of a molecule is a key factor in determining whether or not a substance is polar.

As a result of their unequal charge distribution, polar molecules typically have an asymmetries geometry.

In contrast, the geometry of nonpolar molecules is symmetrical.

Even if a molecule is composed of atoms with varied electronegativity, it is possible for it to be nonpolar due to the dipoles of the bonds being cancelled out by its symmetric structure.

The SF4 molecule’s geometrical structure is depicted below.

Dipole Moment: A molecule’s dipole moment is a measure of its polarity. Polarity is exactly proportional to a molecule’s dipole moment.

It is determined by multiplying the charge on atoms by the distance between the centres of positive and negative charges.

D = Q * R

Attributes of SF4

At normal temperature, sulphur tetrafluoride exists in the gaseous state.

It appears colourless and is regarded highly poisonous.

At 78 degrees Celsius, its density is 1.95 g/cm3.

This material has a melting point of 121.0 °C and a boiling temperature of 38 °C.

At 22 degrees Celsius, the atmospheric pressure of this material is 10.5 atm.

Seesaw is the molecular shape of SF4.

SF4 has a dipole moment of around 0.6322 D.

Utilizations of SF4

Sulfur tetrafluoride is a reagent for preparing organofluorine compounds in organic synthesis.

Fluorination of carbonyl and hydroxyl groups is a common use.

It is also employed in the manufacture of advanced liquid crystal materials for medicine in the biological field.

It is also utilised in the production of insecticides.


Sulfur tetrafluoride is composed of one sulphur atom and four fluorine atoms linked by sigma bonds. The sulphur atom is composed of a single lone pair.

Due to the electrical repulsion between lone pair and bond pair, the form of molecules becomes asymmetric, or seesaw-like.

Due to the difference in electronegativity between fluorine and sulphur atoms, fluorine acquires a partial negative charge whereas sulphur acquires a partial positive charge.

As a result of these properties, sulphur tetrafluoride is a polar molecule.

Therefore, if you have any questions, feel free to post them as comments. I will contact you as soon as possible.

Read more: MO Diagram, SO2 Lewis Structure, Hybridization, and Molecular Geometry

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.


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