BF3 Lewis Structure

BF3 Lewis structure has a total of 24 valence electrons. For the Lewis structure, seven electrons are in the valence shell. To form an octet, a boron needs eight valence electrons. Formal charges may be calculated if you are unsure about the Lewis structure for BF3. As you would expect, the B atom in BF3 only possesses six valence electrons.

BF3 Lewis structure

How to Draw the Lewis Structure?

There are a few aspects of lewis structure drawing to consider:

  • Learn about the periodic table’s properties that aid in determining an element’s atomic number and electronegativity.

  • The number of valence electrons in the final shell of an atom must be counted and calculated.

  • The total amount of valence electrons in a compound may be calculated by multiplying the number of valence electrons on one atom by the number of the same atoms in the molecule.

  • Find the number of lone pairs (unpaired electrons) and the number of electrons that form bonds (electrons that take part in creating a bond).

  • Put the minor electronegative atom in the center of the particles you’ve identified.

  • First, begin by making a single bond with the center atom.

  • Make sure you adhere to the octet rule, which states that each atom must have at least 8 electrons in its final shell.

  • Covalent bonds are formed when two atoms share electrons.

Lewis Structure of BF3

The following are basic suggestions for drawing a Lewis structure step by step. In the following parts of this tutorial, we describe how to design the BF3 Lewis structure in further detail. If you’re a newbie to lewis structure sketching, take your time reading through these parts to get the hang of it.

Number of Electrons in BF3 Valance Shells

Boron is a member of group IIIA. As a result, the final shell of boron has 3 electrons.

Fluorine is a member of group VIIA. Since fluorine contains seven electrons in its final shell, it possesses seven electrons.

3 * 1 = 3 valence electrons provided by the boron atom

For the BF3 structure, the total number of electrons given off by fluorine is 7 x 3 = 21.

The total number of valence electrons is 3 + 21 = 24

Total Pair of Valence Electron

Bonds + bonds + lone pairs at valence shells = total valance electron pairs

The total valence electrons are divided by two to get the total number of electron pairs. There are a total of 12 pairs of electrons in BF3.

Drawing BF3 Central Atom

To be the central atom, you must meet specific prerequisites. To be the center atom, a high valence and the most electropositive atom are critical. Only two components may be used to choose the central atom in BF3. As a result, BH3 has no difficulty deciding on the main bit.

The valence electron of the boron is three. Fluorine has a valence of 1 at its highest. As a result, Boron is contender to serve as the nucleus’ central atom.

The electronegativity values for boron and Flourine are 2 and 4.0, respectively. The more electropositive one is, the more stable it is. Boreal is also likely to be the core atom in this scenario.

Boron is BF3’s core atom because of the features mentioned above.

Atoms with Lone Pairs

On atoms, we’ll begin by labeling lone pairs. In the beginning, bits on the exterior should be denoted with a sole pair symbol ( in this case, fluorine atoms).

There are three B-F bonds. As a result, there are more atoms with nine valence electron pairs.

Make a note of the lone fluorine atom pairs here first. For every fluorine atom, three lone pairs will be required. The nine remaining isolated teams have been depleted. Afterward, all valence electron pairs have been completed, and there are no more lone pairs to be marked on the boron.

Atomic charge

This atom has no charges. The most stable construction does not need decreasing amounts. In other words, we have already discovered the BF3 Lewis structure.


There is a single boron atom in this compound and three fluorine atoms, making it boron trifluoride. BF3’s Lewis structure shows that each fluorine atom has created one bond with a boron atom, as illustrated in the figure. Boron is the central atom of the molecule. BF3’s lewis structure will be explained in detail in this article. Boron has just six electrons around it in its lewis structure. There is still one more octal in the boron atom. Borane BF3 is thus classified as a Lewis acid.

VSEPR Theory of BF3

Boron trifluoride is a relatively uncommon second-period covalent molecule because it defies the octet rule and only possesses six valence electrons. In this case, there are no lone couples. The trigonal geometry is derived from the fact that there are six electrons and three pairs of electrons.

Name Boron Trifluoride
Formula BF3
Central atom Boron
Valence Electron 24
Electron Pair 3

Molecular Geometry of BF3

It is possible to see a molecule’s structure after determining how its electrons have been hybridized in distinct s-orbital and p-orbital kinds, such as sp2 and sp3. BF3, which contains three fluorine atoms and one boron atom, is sp2 hybridized (because of three orbitals).

S-orbital has a sphere form. The 2px and 2py orbitals create head-to-head loops. The electron orbitals (circles) are spaced apart by 120 degrees in the same plane. One electron is assigned to each orbital in an sp2 loop.

BF3’s molecular geometry seems to be trigonal planar based on the structure created in space (three-terminal atoms surround central atoms). It forms an equilateral triangle with 120-degree angles on all sides.

A three-terminal atom’s three-terminal atoms create an equal 120-degree angle with the least electronegative center atom in the case of a lone pair. As a result, at a 120-degree angle, boron single attachments with three fluorine atoms.

BF3 Hybridization

BF3’s molecular structure calls for B atoms to undergo a process known as “hybridization,” in which p and s orbitals are swapped for sp2 hybrid orbitals. The form of a molecule alters because of hybridization.

As per B’s electrical arrangement, two atoms in 1s orbital, two in 2s orbital, and one in p orbital are forming energy levels in the ground state. According to this theory, to go to a higher energy level and include a link with other atoms of F, there is only one accessible electron.

When there are some unoccupied orbitals, electrons may organize themselves by promoting themselves to higher energy levels that are 2p-orbitals to hybridize.

Each of the three orbitals has one electron that may form a single bond now has one electron in each of the three orbitals. sp2 orbitals are formed when s-orbitals and 2p-orbitals combine.

There is still a p-orbital that is vacant as a consequence. There are three hybridized orbitals (2s, 2px, 2py) needed by Boron to form fluorine bonds.

These two types of bonds may be found in molecular arrangements where the initial atoms of the molecule are linked together by the pi () and the pi () bonds, respectively.

Single covalent bonds create the only sigma-bonding molecular structure, and there are no pi-bonding molecular structures.

Polarity of BF3

An electric dipole or multipole moment is meant by polarity when it refers to a separation of electric charge in a molecule or group of molecules. No, not if we’re talking about contradictions. BF3 is not polar. Electronegativity differences of less than 0.5 are considered to be nonpolar.


You may have heard of the C-H bondless chemical molecule. These chemicals are inorganic because they lack carbon and so are not organic. The inorganic component is BF3 or boron trifluoride. It is a colorless, poisonous gas. It emits white vapors in the damp air. It is highly soluble in a colorless liquid (dihydrate.) The BF3 molecule is ‘Trigonal Planar.’ In chemistry, a ‘Trigonal Planar’ model has three atoms surrounding one atom in the center. The 120° bond angles on each of the three atoms make them an equilateral triangle.

Frequently Asked Questions

Here are some FAQs related to BF3 Lewis structure:

1. Who knows what kind of form it has in the molecular structure?

BF3’s molecular geometry is trigonal planar, to be exact. Another feature is that it is a nonpolar and evenly distributed core charge. When all the atoms are arranged in a single plane, the bond angle is 120 degrees. Each of them forms equilateral triangles.

2. What makes BF3 a trigonal planar?

Because it only has three valence electrons, Boron has three-electron pairs with fluorine. These three e- pairs are predicted to form the corners of an equilateral triangle based on repulsion theory (bond angles of 120 degrees). Thus, BF3 is triangular.

3. Is BF3 straight or curved in its path?

The BF 3 molecule’s shape is described as trigonal planar. At the corners of an equilateral triangle, fluorine atoms are arranged in the same way.

4. BrF3 is polar, but why?

BrF3 (bromine trifluoride) is a polar molecule due to the deformation or bending of the molecule’s shape due to two lone pairs on the bromine atom. The BrF3 molecule is polar because the charge distribution between the bromine and three fluorine atoms is not uniform.

5. Why are BF3 and bcl3 nonpolar, respectively?

Because of its very symmetrical form, BF3 (Boron Trifluoride) is Nonpolar. Using the Trigonal Planar geometry, the three BF bonds cancel out each other’s dipole moments, making the compound’s overall Dipole Moment equal to zero.

6. Why is BF3 not a trigonal pyramidal structure?

Because it only has three valence electrons, boron has a three-electron-pair bond with fluorine. These three e- pairs are predicted to form the corners of an equilateral triangle based on repulsion theory (bond angles of 120 degrees). Thus, BF3 is triangular.

7. Bh3 is trigonal and planar, but why?

E. P. G. and molecular geometry may be used to BH3 as an example of E. P. G. The octet rule doesn’t apply to this molecule since it contains just six valence electrons, making it an electron-deficient molecule. At 120o, the hydrogen atoms are the furthest apart they can be.

8. What’s the difference between BF3 and NH3 structures?

As seen in this diagram, the boron’s spin-2 hybridization results in three orbitals that point toward the corners of an equilateral triangle: Thus, the trigonal planar geometry is established.

9. Is BF3 an acid Lewis?

As soon as NH3 contributes its lone pair of electrons, it transforms into BF3, a Lewis acid. The 2p-orbital of BF3 is now filled, and Boron is sp3 hybridized instead of sp2 hybridized earlier (as BF3).

10. What is the reason for the polarity of BF3 bonds?

BF3 (Boron Trifluoride) molecules have three polar B-F bonds. BF3 molecule’s electrons are not evenly distributed between the boron and fluorine atoms but are instead attracted toward the covalent link’s fluorine (F) atom.


As its name suggests, BF3 (Boron Trifluoride) is an inorganic chemical devoid of carbon. As a result, no lone pairs of Boron and Fluorine atoms were formed. Because the three fluorine atoms have a substantially greater electronegativity than the Boron atom, it might be difficult to tell whether BF3 is polar or nonpolar. One can see how many BF bonds there are and how many electrons there are in the Lewis Structure of BF3. It also demonstrated that the central atom has single bonds arranged in a trigonal planar pattern. Because of this, every molecule, algorithm, and method used to create this Lewis Structure complied with all of the chemistry’s rules.

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