N2O4 Lewis Structure & Characteristics (13 Complete Facts)

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N2O4 Lewis structure refers the formation of bonds between participation Nitrogen (N) and Oxygen (O) atoms in Dinitrogen tetroxide (N2O4). Let us define its Lewis structure below.

N2O4 Lewis structure can be described by the method of structuration given by scientist Lewis. This structure denotes the electronic reaction between the N and O atoms of N2O4. The electrons (e–) on this structure are denoted by dots and bonds are imposed by putting dots between the symbols of elements. 

N2O4 Lewis structure benefits with information about the shape, bond angle, hybridisation and many more chemical facts about Dinitrogen tetroxide. Let us signify each of the facts by mentioning the characteristics of the compound throughout this article.

How to draw N2O4 Lewis structure

There are six fundamental step of drawing Lewis structure of any compound, which covers the perfection of the structure in a systematic way. Let us describe them below for N2O4:

Step 1: Calculation of valence electron of the compound

The number of valence electrons enhances the ability among periodic elements to make bonds. These electrons emphasise the bond formation process amidst the atoms. Both Nitrogen and Oxygen atoms shares their valence electrons with each other so counting them is fundamental matter to follow in drawing.

Step 2: Identification of electron needs in valence shell of N and O atoms

Both N and O are noticed to lack electrons in the valence shell from having 8 e–to satisfy octet. After calculating the number of valence electron in last shell it becomes clear that how many e– are needed by the atoms so that they can share that same number of electrons with each other and form bonds.

Step 3: Making relevant choice on central atom among the elements

Least electronegative atoms are the chosen ones for the central position in compounds. In N2O4, Oxygen is more electronegative than Nitrogen. Therefore, two Nitrogen atoms take the middle position in the compound with Oxygen atoms flared out at the terminals.

Step 4: Imposing the bonds between atoms

Lewis structure denotes bonds by 2 electron dots in the middle of elements to signify single bond. In the case of displaying double bonds, 4 dots are put in between N and O atoms. Each N atom makes one sigma bond with each other and single and double bonds with two Oxygen atoms respectively in similar way.

Step 5: Calculation of lone pairs remain in the atoms after making bonds

After displaying the bonds between the elements the remained lone pairs in N and O atoms are needed to be highlighted as well. This is why lone pairs are also counted after bind pairs. In order to show each electron in the compound lone pairs also get priority in the electronic Lewis structure.

Step 6: Formal charge calculation

Formal charge calculation can be considered as an additional step to follow specially for N2O4 as it can be noticed that 2 O atoms and each n atom holds a negative and positive charge respectively in the structure. Those charges internally play effective role to affect the structure.

N2O4 Lewis structure shape

Shape is the physical property of the compound that shares the structure of outer part of them taking idea from Lewis structure. Let us identify the shape of N2O4 below.

N2O4 Lewis structure is shaped as Trigonal planar. It means all the atoms stay in the same plane. Presence of lone pairs makes the bonds fall down a bit. As N atoms in the middle have no lone pairs, the atoms remain steady in their position on same plane without deviated by a few contraction of bond angle.

N2O4 Lewis structure formal charge

Formal charge calculation is significant to identify the existence of internal charges if any remains after binding in the compounds. Let us find the same for N2O4.

Formal charge of N2O4 Lewis structure is zero. This can be calculated by following the formula Formal Charge = number of valence electrons – number of nonbonding electrons – number of electron shared (number of bonding electrons/2)

A complete calculation is displayed over the table below:

Elements and
the number of
their valence electrons		Number of
nonbonding electrons		Number of
electron shared		Formal charge
N1 = 50-1 (Extra electron left) = -14/2 = 2(5-(-1)-2) = 4
N2 = 50-1 (Extra electron left) = -14/2 = 2(5-(-1)-2) = 4
O1 = 642/2 = 1(6-4-1) = 1
O2 = 642/2 = 1(6-4-1) = 1
O3 = 64+1(extra electron gained)  = 5½ = 0.5(6-5-0.5) = 0.5
O4 = 64+1(extra electron gained)  = 5½ = 0.5(6-5-0.5) = 0.5
N2O4 = 34(4-4-1-1-0.5-0.5) = 0
Formal charge calculation of N2O4 Lewis structure

N2O4 Lewis structure angle

Angle is also a physical property of compound that elaborates the angle between bonds created by the elements let us find the bond angle of Dinitrogen tetroxide.

N2O4 has approximately 126o of bond angle.  This has been identified as slightly deviated from its ideal bond angle, which should be 120o. The compound holds it according to its geometric shape where the bond length of N-N bond is very large which values 175 pm.

N2O4 Lewis structure octet rule

Octet rule provides the theory of having eight electrons in valence shell anyhow by the periodic elements. Let us find how N and O atoms in N2O4 follow this rule.

N2O4 tries to follow octet rule by making eight electrons in the valence shell. N atoms in the molecule are found to be distracted from octet rule by having six electrons after making bonds with O atoms. 2 O atoms are noticed to fill octet with the help of electrons shared by N atoms.

n2o4 lewis structure
N2O4 Lewis structure bonds from Wikimedia Commons

Other 2 O atoms are noticed to make single bonds with N atoms where they lack one electron from making it eight so they show tendency of adopting free electrons, which is denoted by –ve sign in the molecule over those O atoms.  N atoms use to hold +ve charge as it show tendency of leaving the extra free electron after bonding.

N2O4 Lewis structure lone pairs

Lone pair calculation relevantly imposes the knowledge about non-participated electrons in binding. Let us calculate the number if lone pairs in N2O4.

N2O4 Lewis structure holds total 20 lone pairs. All the lone pairs exist in O atoms. 2 O atoms having negative charge displays 6 lone pairs on each and other 2 O atoms having double bonds with n atoms have two lone pairs on each. This lone pairs also stay in the same plane with the atoms in N2O4.

N2O4 valence electrons

Valence electrons exist in the last energy level of periodic elements. The count of these electrons signifies electron needs amidst them. Let us calculate this number of N2O4.

The total number of valence electron in N2O4 is 34.

  • The number of valence electron in each N atoms = 5
  • The total number of valence electron in 2 N atoms = (5*2) = 10
  • The number of valence electron in each O atoms = 6
  • The total number of valence electron in 4 O atoms = (6*4) = 24
  • The total number of valence electron in N2O4 = (10+24) = 34

N2O4 hybridization

Hybridisation is the state of orbitals in elements after they bonded with others. The orbitals change after overlapping with each other’s. Let us find hybridisation of N2O4.

N2O4 is a sp2-hybridised molecule.  Both N and O atoms are noticed to have sp3 hybridisation. After making bond with O atoms central N atom leaves one extra electron it holds in 3p orbital, which gives it sp2 hybridisation in its combined state.

Steric number is also a fact, which supports the hybridisation. This number is calculated by adding the number of lone pairs and bonds pairs of the central atoms. As the central N atom has 0 lone pair and 3 bond pairs, its steric number is 3, which signifies its sp2 hybridisation state.

N2O4 solubility

Solubility differs on the nature of solvent. Generally, polar solvents like water are taken to measure solubility of compounds. Let us check solubility of N2O4.

N2O4 is not soluble in water or any other compound rather it undergoes reaction with water. This is due to its ionic structure with a balancing feature. The compound gives out Nitrous and Nitric acids in reaction with water and HCl and this product supports the fact that N2O4 is not directly soluble in water.

Is N2O4 solid or liquid?

Solid or liquid state is quite depending on the bond strength of the compounds. Let us signify the natural state of N2O4 in this section.

N2O4 is a red-brown liquid substance with a sharp odour, which has low bond strength.  Therefore, the internal attraction force between the N and O atoms are less, which cannot afford compact structure of the compound. The loosely bonded atoms make it liquid.

Is N2O4 polar or nonpolar?

Polarity depends on the structural format of the compound such as symmetric or asymmetric. Therefore, let us find the structure format of N2O4 and justify its polarity below.

N2O4 is a non-polar compound. The molecule bonds the elements in the same plane, which is a positive factor that balances the internal effects of lone pair. Moreover, the symmetric structure of the molecule is capable of cancelling out its dipole moment and makes it non-polar.  

Is N2O4 acidic or basic?

Acidic or basic nature is defined by the capacity of accepting electrons by the atoms in a compound. Let us find if N2O4 is acidic or basic.

N2O4 is highly acidic compound. The central Nitrogen atoms have enough capacity to give place to electron pairs. Moreover, the negative charge of two Oxygen atoms also indicates that they already have acceptance capacity for new electrons.  These facts of the compound are supporting its acidic behaviour.

Is N2O4 electrolyte?

Electrolytes must have enough charge density inside with ionic behaviour to conduct electricity with the help of free electrons. Let us define this fact for N2O4.

N2O4 can be considered as electrolyte. The formation of the compound may denote its neutral structure but inside the compound, there is a huge charge density within N and O atoms. These charges have capacity to carry electricity in the molten state after reacting with water molecules.

Is N2O4 ionic or covalent?

Ionic and covalent nature of molecules refers to the bonding style chosen by the participative elements. Let us identify the bonding style followed by N2O4.

N2O4 is a pure covalent molecule. The electron sharing method of binding by Nitrogen and Oxygen atoms makes this compound. In satisfying each other’s octets the elements shares their valence electrons with each other partially so that the bond could be formed with cooperation of valence electrons.  

Conclusion

This article has signified the fact of having unique compound structure with covalent bond and insider charge density. The non-polar nature of N2O4 has been recognised as the effect of its shape, which has covered a single plane. The compound has been introduced with its toxic acidic behaviour as well. 

Read more about 11 Facts on H2SO4 + Al(OH)3.

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