Phosphorus trifluoride shows up as a colorless gas and it is extremely toxic in nature similar to carbon monoxide or equivalent to phosgene. It is odorless, nucleophile, and also weak basic in nature and has a chemical formula of PF3.

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In this article, us will comment on Phosphorous trifluoride (PF3) lewis dot structure, molecule geometry, electron geometry, hybridization, polar or nonpolar, its link angle, etc.

“Phosphorus trifluoride is comparable to carbon monoxide in that it is a gas i beg your pardon strongly binding to iron in hemoglobin, avoiding the blood from absorbing oxygen.”

Properties the Phosphorous trifluoride

It has a molar mass of 87.96 g/mol.It has actually a boiling suggest of −101.8 °C and also a melting allude of −151.5 °C.It has a dipole minute of 1.03 D.It is non-flammable gas.It is a highly toxic gas and reacts progressively with water
Name that MoleculePhosphorous trifluoride
Chemical formulaPF3
Molecular geometry/shape that PF3Trigonal pyramid
Electron geometry that PF3Tetrahedral
Bond angle96°
Total Valence electron for PF326
The formal fee of PF30

Page Contents present
1 exactly how to attract lewis structure of PF3
2 basic steps for illustration the Lewis dot framework for PF3
3 What room the electron and also molecular geometry the PF3?
4 Hybridization that PF3
5 The bond edge of PF3
6 Phosphorous trifluoride polarity: is PF3 polar or nonpolar
7 Three factors that indicate the polarity that PF3
9 review

How to draw lewis framework of PF3

PF3 lewis framework is comprised of one phosphorous atom that located at the central position and also three fluorine atom that spread about the main atom. There are a full of 10 lone pairs(including main and terminal atoms) and also three bonded pairs current in the lewis dot framework of PF3.

Let’s see how to draw the lewis structure of PF3 by following some straightforward steps-

Simple actions for illustration the Lewis dot structure for PF3

1. Count total valence electron in PF3

In the first step, we have to find how countless valence electrons are there in PF3, so the we deserve to distribute castle around main and terminal atoms with the goal of completing their octet shell.

You have two ways to uncover out the valence electron for a particular atom, either by feather at their periodic group or by creating their digital configuration. Us will use the method of the periodic team for detect the valence electron in PF3.

Phosphorous atom belongs to Group 5A or 15A in the routine table, hence, it has a 5 valence electron in the outermost shell whereas fluorine atom belongs to Group 7A or 17A, hence, it has actually a 7 valence electron in its outermost shell.

⇒ total valence electron in Phosphorous = 5

⇒ complete valence electron in Fluorine = 7

∴ complete valence electron available for illustration the PF3 lewis structure = 5 + 7*3 = 26 valence electrons  <∴PF3 has three fluorine atom and one phosphorous>


2. Uncover the least electronegative atom and also placed it in ~ center

Which is an ext electronegative, phosphorous or fluorine atom? that course, the fluorine atom(3.98) is much more electronegative 보다 phosphorous(2.19). Hence, the fluorine atom goes external in the lewis diagram conversely, the phosphorus atom fetched the seat of the central position.


3. Affix phosphorous and fluorine with a single bond

In this step, we start illustration the PF3 skeletal framework by bonding with each other Phosphorous and Fluorine with a single bond.


Now look at this structure and count how countless electrons we used till now and how countless are left. 

As three solitary bonds are offered in the over structure that includes 6 electrons and also we have actually a total of 26 valence electron are obtainable for drawing the PF3 lewis structure.

∴ (26 – 6) = 20 valence electrons

So, we are left with 20 valence electrons.

4. Put remaining valence electrons beginning from outer atom first

In this step, we need to place the remaining valence electrons beginning from the more electronegative atom or native the outer atoms.

So, fluorine is an ext electronegative 보다 phosphorous and it demands 8 electron to finish its octet rule.

Fluorine atoms currently sharing 2 electrons v the help of a single bond so the only requirements 6 an ext electrons to complete its octet rule.


As you view in the above structure, every fluorine has 6 electrons represented as dots and 2 electron in form of a solitary bond, hence, the fluorine atom has a complete of 8 electrons and it completed its octet comfortably.

Now find how countless valence electrons space left.

Three fluorine atom in the over structure offered 18 electrons(represented together dots) from a full of 20 staying valence electrons.

∴ (20 – 18) = 2 valence electrons

So, us left with just 2 electrons.

5. Complete main atom octet and use covalent shortcut if necessary

We are left with just 2 valence electrons and by looking at the 4th step structure, we see, the main atom phosphorus has only 6 electrons(three solitary bonds), hence, it requirements 2 an ext electrons to finish the octet and also attains stability.

So, put the remaining two electrons on the phosphorous atom and also complete that octet.


Lewis dot structure for PF3

As you check out in this PF3 lewis dot structure, phosphorous and fluorine completed their octet, and everything looks fine, but, for the benefits of satisfaction, we should also determine the formal fee in the over structure to recognize whether that is steady or not.

6. Check the security with the help of a formal fee concept

To calculation the formal charge in the PF3 lewis structure. Usage the formula provided below-


Let’s begin with the central atom i m sorry is phosphorous in the PF3 molecule.

For phosphorous atom:

⇒ Valence electron of phosphorous = 5

⇒ Lone pair electrons on phosphorous = 2

⇒ Bonding electrons of phosphorous(3 solitary bonds) = 6

∴ (5 – 2 – 6/2) = 0 formal charge on the phosphorous main atom.

Each fluorine atom in the PF3 lewis structure has actually the same number of lone pair and also bonded pair electrons, hence, just count formal fee for simply one fluorine atom

 For fluorine atom

⇒ Valence electron of fluorine = 7

⇒ Lone pair electron on fluorine = 6

⇒ Bonding electrons approximately fluorine (1 solitary bond) = 2

∴ (7 – 6 – 2/2) = o formal fee on each fluorine atom.

Hence, every atom in PF3 gets a formal fee equal come zero.


Therefore, the above lewis framework of PF3 (phosphorous trifluoride) is the most stable and reliable

The molecule geometry of PF3 is a trigonal pyramid and also its electron geometry is tetrahedral due to the fact that phosphorous has actually Sp³ hybridization through 5 valence electrons in its valence shell and it provides three bond pairs, one v each fluorine atom.

And one lone pair is existing on the central phosphorous atom that tries to repel the bonded bag of electrons, together a result, the adjacent atoms press apart offering its geometry trigonal pyramid.


As you watch in the above structure, the lone pair on the phosphorus atom defeat the surrounding electron pairs, together a result, the two fluorine atom in equatorial place pushes much apart offering the molecule geometry that PF3 exact same as a trigonal pyramid.

Let’s see how to uncover the molecular and electron geometry the PF3 using the VSEPR chart and also AXN notation.

AXN technique is a famous method of identify the molecular and electron geometry using the VSEPR chart.


AXN notation because that PF3 molecule:

A denotes the main atom, so, in the PF3 molecule, phosphorous is the central atom. A = PhosphorousX denotes the bonded atoms to the central atom, together we know, phosphorous is bonded with 3 fluorine atoms. Therefore, X = 3N denotes the lone pair top top the main atom, as per PF3 lewis structure, phosphorous has only one lone pair. Hence, N = 1

So, the AXN notation because that the PF3 molecule i do not care AX3N1

As every the VSEPR chart, if a molecule central atom is fastened with three bonded atoms and has had only one lone pair ~ above the central atom then the molecule geometry of the molecule is the trigonal pyramid in nature, and also electron geometry is tetrahedral.


Hence, the molecular shape for PF3 is a trigonal pyramid and also its electron geometry is tetrahedral.


PF3 molecule geometry/shape

Hybridization the PF3

Let’s discover the hybridization of PF3 through the steric variety of its main atom.

“Steric number is the addition of a total variety of bonded atoms roughly a main atom and also the lone pair current on it.”

∴ Steric variety of PF3 = (Number the bonded atoms attached to phosphorous + Lone pair top top phosphorous)

As per the lewis structure of PF3, the central phosphorous atom is bonded with 3 fluorine atoms and also it has one lone pair also.

∴ Steric variety of PF3 = (3 + 1) = 4

Steric numberHybridization

So, for a steric number of four, we acquire the Sp3 hybridization top top a phosphorous atom in the PF3 molecule.

The newly produced hybrid orbitals in PF3 molecule have actually 25% behavior of the s orbital and also 75% actions of the p orbital.

The bond angle of PF3

“Phosphorus trifluoride has an F−P−F bond edge of approximately 96°“.


PF3 is a polar molecule due to the fact that of that asymmetric shape and electronegativity difference between phosphorous and fluorine which cause non-zero dipole moment.

For knowing, is PF3 polar or non-polar? we will comment on three determinants 1. electronegativity 2. dipole moment 3. Geometrical or molecule shape.

Three factors that show the polarity the PF3 

1. Electronegativity: 

The difference in between the electronegativity the Phosphorous and also fluorine is straight proportional come the Polarity that the PF3 molecule.

The electronegativity that the fluorine atom is 3.98 and also for the phosphorous atom, its value is 2.19.

So, being an ext electronegativity of fluorine help it come attract an ext bonded electron 보다 phosphorous. Therefore, fluorine gains a partial negative charge, and also phosphorous profit a partial confident charge.

Positive and negative charges cause non-uniform charge distribution approximately the PF3 structure. Hence, it additionally causes PF3 to come to be polar in nature.

Also, the electronegativity difference of fluorine and phosphorous atom is higher than 0.5 which ensures that PF3 is highly polar in nature follow to the Pauling scale.

2. Dipole moment

The network dipole moment of the PF3 molecule is 1.03 D. Dipole moment measure the toughness of polarity. 

The bigger the electronegativity distinctions of atoms greater is the polarity and dipole moment.

The dipole the the PF3 molecule originates in the downward and also upward direction since of the lone pair current in Phosphorous. Hence, it causes a non-zero dipole moment which reasons the polar nature that PF3.

⇒ Dipole minute formula = fee on the atoms * the distance in between them 

∴ D = Q × R

3. Geometrical or molecule shape

The geometrical form is additionally a huge factor to determine is PF3 polar or non-polar.

As we know molecular geometry the PF3 is trigonal pyramidal i m sorry is asymmetric and also when the form of the molecule is asymmetric or distorted it doesn’t cancel the dipole moment throughout the molecule. Hence, reason polar nature the the molecule

All these factors are sufficient to recognize why PF3 is polar in nature.


Why bond edge in PF3 higher than PH3?

This is because, in the PF3 molecule, earlier bonding occurs.

“The exchange of electrons in between an atomic orbital ~ above one atom and also an antibonding orbit on one more atom is well-known as ago bonding.”

Due to earlier bonding, greater bond pair-bond pair repulsion exist in PF3 보다 PH3.

Hence, the greater the repulsion between bonded pairs, the bigger is the shortcut angle.

Also, in the PF3 molecule, fluorine is a very electronegative atom and also it fetched an ext electrons in the direction of itself which likewise creates much more repulsion, and also this causes, widening the bond angle in PF3. 

The almost right bond angle of PH3 is 93° and also for PF3, that is 96°.

How many lone pairs and also bond pairs room present roughly Phosphorous in the PF3 lewis structure?

According to the lewis dot structure of PF3, Phosphorous contains 1 lone pair and also 3 bonded pair i beg your pardon is enclosed with 3 fluorine atoms.

How does the PF3 lewis dot framework obey the octet rule?

If an atom gets an ext or less than 8 electrons in an outermost shell then we deserve to say that atom violates the octet.

Phosphorous atom has 5 valence electrons in its outermost shell and also it is capable of creating three covalent bonds v the bordering atom to finish its octet.

Whereas the fluorine atom has 7 valence electrons and is qualified of developing only one covalent bond with various other atoms.

Therefore, in the PF3 lewis structure, phosphorous together a main atom creates three covalent bond (one through each fluorine atom) and fulfills that is octet need whereas the fluorine atom additionally completes the octet by one covalent link attached through the main atom.

∴ every atoms in the PF3 lewis dot structure get specifically 8 electrons in their octet, hence, they are obeying the octet rule

Why is the molecular geometry that PF3 is trigonal pyramid vice versa, its electron geometry is tetrahedral?

This is since there is a slight difference in molecular and electron geometry. Molecular geometry takes only bonded atoms into account when calculating the shape of any type of molecule.

Whereas the electron geometry considers both bonded atoms and also lone pairs while predicting the geometry of any type of molecule.

The phosphorous central has 4 regions of electron density(one lone pair + 3 bonded pairs) hence, as per VSEPR theory, the electron geometry of PF3 is distorted tetrahedral.

Whereas the molecular geometry the PF3 is trigonal pyramidal that has actually one atom at the center and three atom at the trigonal base corners and it is comparable to a tetrahedron but it does not take into consideration lone pair.

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The total valence electron accessible for illustration the PF3 lewis framework is 26.The steric number of the main atoms in phosphorous trifluoride is 4 that ensures the it has actually an Sp3 hybridization.PF3 is polar in nature because of its distorted form that causes uneven charge circulation all end the atom leads to a non-zero dipole moment and makes that polar in nature.The molecular geometry or shape for PF3 is the trigonal pyramid.The electron geometry because that PF3 is tetrahedral together it main has 4 areas of electron density.Lewis dot framework of PF3 includes 1 lone pair on the main atom(phosphorous) and 3 lone bag on each external atom(fluorine).