NF3 lewis structure: Drawings, Hybridization, Shape, Charges, Pairs


We’ll talk about  NF3 lewis structure, formal charges, geometry, hybridization and uses of NF3 in this article.

Nitrogen trifluoride (NF3) is an inorganic, colourless, non-flammable, toxic gas with a slightly musty odour. In the NF3 molecule, nitrogen is attached to three fluorine atoms via a single bond and has a molecular weight of 71.00 g/mol.

How to draw the NF3 lewis structure?

Let’s draw the NF3 lewis structure step by step;

First count the number of valence electrons in the molecule NF3

N ( Z= 7) = [He] 2s22p3  ie 5 valence electrons are present

Since in the outermost shell of the nitrogen 5 electrons are present

F  (Z = 9) = [He] 2s22p5  ie only 7 electrons are avaible for bonding

Total valence count =  5 + 7*3 = 26 valence electrons.

Before arranging the atoms, one should know which atom will occupy the central position. As per the electronegativity rule, the atom with a less electronegative nature will take that position. Hence, Nitrogen will place at the center, and the rest of the atoms will take peripheral positions.

Positions of atoms
  1. As per the sigma bonding rule, we will first make a single bond between the atoms and then proceed with the further arrangement. 
Arrangement of atoms
  • After making the single bond, it’s time for arranging the rest of the electron pairs as one bond = 2 electrons ie 6 electrons out of 26 electrons are already arranged. Hence, we left with 20 electrons. Let’s assign further electrons to get a clear picture of the NF3 lewis structure.
nf3 lewis structure

                                                         NF3 lewis structure.

NF3 valence electrons

As explained in the first step of lewis’s structure, the valence electrons are those which are available for bonding. Also, the valency of an atom is decided by its number of electrons in the outermost shell.

Why only outermost electrons only considered valence electrons?

 Let’s understand this by taking the example of a nitrogen atom. As nitrogen belongs to group 15 and has an atomic number of seven . The electronic configuration of the nitrogen:

N ( Z=7) =  1s2 2s2 2p3

 As it can be seen, the electrons in 1s2 orbitals are the closest to the nucleus and therefore, there is a requirement for more energy to remove them; in other words, they are stable and hence cannot be removed.

However, only the outermost electrons can remove easily and participate in bonding. Likewise, in the case of fluorine (F (Z= 9) = 1s2 2s2 2p5), inner-most orbitals do not participate in bonding and only 7 electrons in the outermost are left for bonding. Now, as discussed above there are 26 valence electrons are available in the NF3 molecule.

NF3 lewis structure octet rule

Every atom wants to achieve stability; in terms of chemistry, stability refers to the stable electronic configuration. Hence, every individual atom intends to attain the noble gas electronic configuration because noble gases have fulfilled outermost electronic shells which are accountable for their stability. This is known as the octet rule.

Let’s examine whether the NF3 lewis structure obeys the octet rule or not?

As referred to in figure number 2, nitrogen has 8 electrons after bonding. Similarly, each F atom also has 8 electrons count in their outer shells. It indicates the fulfilment of the octet rule.

NF3 lewis structure lone pairs

 Lone pairs belong to that category of electrons that are available for bonding but do not participate during bond formation.  Again referring to the pictorial representation of the NF3 lewis structure (figure 2), there is only one lone pair present on the nitrogen atom whereas the fluorine atom has 6 unbonded electrons.

NF3 lewis structure formal charge

The formal charge can be calculated by the formula given below:

Calculation of formal charge for Nitrogen atom

Valence electrons = 5 ( as belong to second group)

Unbonded electron count = 2

Bonded electrons = 6

F.C =  5 – 2 –  6/2 =  0

Calculation of formal charge for fluorine  atom

Total valence count = 7

Unbonded electron count = 6

Bonded electrons = 2

F.C = 7 -6 – 2/2 =  0

Hence total formal charge = 0

NF3 lewis structure resonance

Can NF3 show resonance?

Generally, resonance just refers to the movement of electrons from one palace to another place. However, in the NF3 lewis structure, resonance is not possible because there are no empty orbitals left in Fluorine orbitals so that lone pair of nitrogen can participate

NF3 hybridization

The process of hybridization solves the mystery behind the formation of molecules.  Let’s understand the intermixing of nitrogen and fluorine atoms of NF3 step by step

  1. The electronic arrangement of electrons of both participation electrons in their  ground  state is given below :
Ground state arrangement
  • 2. The electronic arrangement of electrons of both participation electrons in their  excited state is given below
Excited state arrangement
  • 3. Formation of NF3
      Formation of NF3

NF3 lewis structure shape

The shape of NF3 is an important aspect here. As we already know, the hybridization of NF3 is SP3. Therefore it is expected that the shape of the NF3 is tetrahedral. However, this is not the scenario here. The shape of NF3 is trigonal pyramidal in nature. This is due to the presence of lone pair on the nitrogen atom, as we saw in the NF3 lewis structure.

The trigonal pyramidal shape of NF3  ( Wikipedia)

NF3 lewis structure angle

 As shown in the above figure, the bond angle is about 102.5o in NF3 as the molecular geometry is trigonal pyramidal and has a lone pair due to which the standard tetrahedral angle of 109o has deviated and decreased to 102.5o.

NF3 uses

Nitrogen trifluoride is primarily used for manufacturing microelectronics such as LCDs and thin-film solar cells, as semiconductors used in these devices are made up of nitrogen trifluoride.

NF3 is used in chemical lasers such as hydrogen fluoride and deuterium fluoride lasers.

The major application of NF3 is in the silicon removing process. It has the advantage of less residual contamination and dissociates easily compared to perfluorinated compounds  and  sulfur hexafluoride at low pressures. Apart from it, NF3 is also considered an eco-friendly substitute for SF.

NF3 is used in the fabrication process and also for cleaning PECVD chambers.

NF3 is used as a stable fluorinating agent

Frequently asked questions

 IS  NF3 a greenhouse gas?

NF3 is considered a greenhouse gas because it absorbs infrared radiation very rapidly emitted by the earth which leads to it being a potent greenhouse gas.

Is NF3 polar or non polar?

NF3  is polar as it is unsymmetrical and hence the bonds do not cancel out each other. Therefore NF3 is polar in nature.

Is NF3 toxic in nature?

It comes under the non-toxic category. However, sometimes when it gets into contact with the eyes it irritates and also disturbs mucous membranes but NF3 is less toxic than the oxides of nitrogen.

Give physical properties of NF3

  • It  is colourless
  • Non-toxic
  • Exist as gas in nature with a mustardy odour

IS NF3 covalent in nature?

Yes, it is covalent in nature as both the atoms Nitrogen and fluorine are non-metals. Therefore, the bonding which can establish between them is covalent only.

Give a reaction where NF3 act as an oxidizing agent

    It oxidizes hydrogen chloride to chlorine:

   2 NF3 + 6 HCl → 6 HF + N2 + 3 Cl2

How does NF3 react with steel?

NF3 is compatible with steel and with plastics also. It converts itself into tetrafluorohydrazine when it comes in contact with any metal. For example:

    2 NF3 + Cu → N2F4 + CuF2

Give an equation where NF3 convert into tetra ammonium salts

Nitrogen fluoride reacts to give ammonium salts with SbF5 as shown above:

NF3 + F2 + SbF5 → NF+4SbF6

Pomila Sharma

Hello...Myself is Pomila Sharma. I have done my master's in Chemistry with a specialization in synthetic organic chemistry. I have published 4 research articles. I am very passionate about the chemistry world. I believe it's all about chemistry so let’s explore it together. LinkedIn link: https://www.linkedin.com/in/pomila008

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