Formaldehyde is an organic compound that shows up as a colorless gas with the chemistry formula CH2O. That is the easiest aldehyde made up of two hydrogens, one carbon, and also one oxygen. That is widely supplied as a preservative due to the fact that of that is antibacterial properties.

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In this article, we will study Formaldehyde (CH2O) lewis structure, molecule geometry, link angle, hybridization, polar or nonpolar, etc.

Formaldehyde is offered to deal with or law cells and also tissue. The has great antimicrobial properties and its aqueous solution is offered as a disinfectant to kill bacteria and also fungi.

Properties that Formaldehyde

It has actually a molar fixed of 30.02 g·mol−1.It is dissolve in water and acetone.It has a boiling point of −19 °C and a melting suggest of −92 °C.In pure form, that smells pungent.
Name of MoleculeFormaldehyde
Chemical formulaCH2O
Molecular geometry the CH2OTrigonal planar
Electron geometry of CH2OTrigonal planar
NaturePolar molecule 
Total Valence electron because that CH2O12

Page Contents present
1 how to attract lewis structure for CH2O
2 monitor some actions for drawing the lewis dot framework of CH2O
3 What space the electron and molecular geometry that CH2O?
4 What is the Hybridization the CH2O?
5 What is the bond angle of CH2O?
6 Formaldehyde polarity: is CH2O polar or nonpolar?
7 Two factors that show the polarity of CH2O
9 review

How to draw lewis framework for CH2O

The lewis structure of CH2O is consisted of of one carbon, one oxygen, and also two hydrogens. This atoms space structured in a method that, the carbon atom is preserved in a main position and it is linked with two hydrogens with a single bond and double-bonded with an oxygen atom.

There room a full of 2 lone pairs and also 4 bonded pairs(two solitary bonds + one double bond) present in the lewis framework of CH2O.

Let’s take it a look at at just how to attract the lewis dot framework of CH2O v some basic steps.

Follow some measures for illustration the lewis dot structure of CH2O

1. Count total valence electron in CH2O

As we know, the lewis chart is all about representing the valence electron of atom within the molecule. Valence electrons are the outermost electron of one atom that deserve to participate in the bond development either by donating or accepting.

So, in the an initial step, us will find the complete valence electron that CH2O. To calculate this, look at the periodic team of carbon, hydrogen, and also oxygen.

The carbon atom belonging to group 4A or 14th in the regular table, hence, it has actually 4 valence electrons. The oxygen atom belongs to group 6A or 16, hence, it has a 6 valence electron vice versa, the hydrogen atom is positioned at group 1A, for this reason the variety of the valence electron in hydrogen is 1.

⇒ Total number of the valence electrons in carbon = 4

⇒ Total variety of the valence electrons in oxygen = 6

⇒ Total variety of the valence electron in hydrogen = 1

∴ Total variety of valence electrons easily accessible for illustration the Lewis structure of CH2O = 4 + 1(2) + 6 = 12 valence electrons  <∴CH2O molecule has one carbon, one oxygen, and two hydrogens>


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

This step can be tricky sometimes however in the case of the CH2O molecule, the is really easy to determine the least electronegative atoms because that placing at the main position in the lewis diagram.

One should remember that the hydrogen atom have the right to never take it the place of central in the lewis diagram due to the fact that it have the right to have just a best of 2 valence electron in its external shell, hence, it have the right to never have the ability to share much more than 2 electrons if required.

As main position requirements the atom i m sorry is more prone to share the electron with various other atoms. The electronegativity that the oxygen atom is 3.44 and for the carbon atom, that is 2.55.

Hence, placed the carbon at main position whereas spread the oxygen and hydrogen atom evenly roughly it.



3. Connect outer atoms to central atom v a solitary bond

In this step, sign up with together each outer atom(oxygen and hydrogen) come the main atom(carbon) with the aid of a solitary bond.


Now we will certainly count how plenty of valence electron we provided in the over structure. In the above structure, we have used three solitary bonds native connecting two hydrogen atoms and also one oxygen atom to the central atom(carbon).

A solitary bond method two electrons, hence, (3 solitary bonds × 2) = 6 valence electron are offered from a full of 12 valence electrons the are easily accessible for illustration the Lewis framework of CH2O.

∴ (12 – 6) = 6 valence electrons

So, we room left v 6 valence electrons more.

4. Ar remaining valence electrons starting from external atom first

Now we will start putting the continuing to be valence electrons to the external atoms for completing their octet. In a CH2O molecule, the oxygen and also hydrogen atoms space the external atoms.

The hydrogen atom only requirements two valence electron to finish its octet and also attains stability, moreover, the oxygen atom requirements 8 electrons for completing the octet and coming in a stable form.

If friend look at the 3rd step structure, both hydrogen atoms already getting the 2 electrons in their outer shell in type of a solitary bond, hence, both these already completed their octet.

So, just put the continuing to be valence electron end the oxygen atom it spins it’s complete the octet shell.


So, by looking in ~ the above structure, we view the oxygen atom has 8 electrons(6 electrons stood for as dots + 2 electrons in a single bond associated to it) in that octet shell. Hence, it additionally completed its octet.

In the above structure, we have used a total of 12 valence electrons(three solitary bonds the contain 6 electrons and also 6 electrons as dots). Hence, now we have no valence electron left.

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

The central atom in the CH2O molecule is carbon which likewise needs 8 electron in its external shell for completing the octet. In the 4th step structure, we view the carbon atom has actually 6 electron in its external shell in kind of three single bonds but it requirements 2 much more electrons for completing the octet.

But the trouble is we don’t have any kind of remaining valence electrons, therefore, in this situation, us will transform the one lone pair the oxygen atoms into a single covalent bond.


As you check out in the above structure, us have successfully converted the one lone pair of oxygen atom to a covalent bond, hence, the carbon central also perfect its octet as it has actually 8 electrons(two solitary bonds + one dual bond) in its valence or external shell.


That’s it, as we watch in the over CH2O lewis structure, all atoms(hydrogen, oxygen, and carbon) completed their octet.

Before, heading to the next part, we should check the stability of the over CH2O lewis framework with the help of the formal fee concept.

6. Examine the stability with the help of a formal charge concept

“The lesser the formal charge on atoms, the better is the stability of the lewis diagram.”

To calculate the formal fee on one atom. Use the formula offered below-


Let’s start with the central atom i m sorry is carbon in the CH2O molecule.

For carbon atom:

⇒ Valence electron of carbon = 4

⇒ Lone pair electron on carbon = 0

⇒ common pair electrons around carbon(two solitary bond and also one double bond) = 8

∴ (4 – 0 – 8/2) = 0 formal fee on the carbon central atom.

 For oxygen atom

⇒ Valence electrons of oxygen = 6

⇒ Lone pair electron on oxygen = 4

⇒ shared pair electrons around oxygen (1 dual bond) = 4

∴ (6 – 4 – 4/2) = o formal charge on the oxygen atom.

 For hydrogen atom

⇒ Valence electron of hydrogen = 1

⇒ Lone pair electron on hydrogen = 0

⇒ mutual pair electrons about hydrogen (1 single bond) = 2

∴ (1 – 0 – 2/2) = o formal fee on both hydrogen atoms.

So, every atom(oxygen, hydrogen, and also carbon) in the CH2O lewis framework gets a formal fee equal to zero.


Therefore, the over lewis framework of CH2O is most appropriate, reliable, and also stable in nature due to the fact that the as whole formal fee is zero.

The molecule geometry that CH2O is trigonal planar as the carbon main atom has actually no lone pair and is attached come the two hydrogens atoms and one oxygen atom with the assist of two solitary bonds and one dual bond. So, there space three regions of electron density around the carbon main atom.

“A region of electron density way the team of bonding or nonbonding electrons the present around the atom. The solitary bond, dual bond, or also triple bond around the atom will certainly be counted together one region.”


The electron pair approximately the carbon central atom will repel each other and tried to go much from each other, they will take the position where repulsion becomes minimum in between them.

According come the VSEPR theory, the central atom v three areas of electron thickness adopts a trigonal planar geometry since repulsion is minimum in electron pairs at this position.

Hence, the last molecular geometry that CH2O shows up as a trigonal planar.

The electron geometry of CH2O is also trigonal planar because there is no lone pair present on the central atom(carbon), hence, just bonded pair will certainly be counted for determining the shape of CH2O.


CH2O molecular geometry

We can also find the electron and also molecular geometry the CH2O making use of the AXN an approach and VSEPR chart.


AXN is a an easy formula the represents the number of the external inspection atom and lone pair ~ above the central atom to predict the form of the molecule utilizing the VSEPR chart.

AXN notation for CH2O molecule:

A denotes the central atom, so, carbon is the central atom in CH2O molecule A = CarbonX denotes the bonded atoms to the central atom, carbon is bonded through two hydrogen atoms and one oxygen atom. Therefore, X = 3N represents the lone pair on the central atom, as per CH2O lewis structure, the carbon main atom has actually zero lone pair. Hence, N = 0

So, the AXN generic formula for the CH2O molecule i do not care AX3N0 or AX3.

As per the VSEPR chart, if a molecule gets AX3 generic formula then its molecular geometry will certainly be trigonal planar and electron geometry will also be trigonal planar.

Look at the VSEPR chart listed below to clear her doubts.


What is the Hybridization that CH2O?

“Hybridization is a concept that helps us understand the form of molecular orbitals top top bonding to because that compounds”

We will certainly not walk for the deep touch of the hybridization concept, we just want to know just how to discover the hybridization of the CH2O molecule.

Just record the steric number of the CBr4 molecule to gets it hybridized.

The steric number is merely an addition of external inspection atom attached to the central atom and also a lone pair current on the central atom.

∴ Steric variety of CH2O = (Number the bonded atoms attached come carbon + Lone pair top top carbon atom)

According to the lewis structure of CH2O, the carbon main atom is bonded v two hydrogen atoms and one oxygen atom and also it consists of no lone pairs.

∴ Steric variety of CH2O = (3 + 0) = 3

Steric numberHybridization

So, we gain the Sp2 hybridization for the CH2O molecule since the steric number because that the carbon central atom is 3.

“The process of intermixing that one S and also two ns orbitals to give three identical hybrid orbitals is known as Sp2 or trigonal hybridization. Sp2 has 33% s and also 67% ns character.”


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What is the bond angle of CH2O?

Every atom in the CH2O molecule has a bond angle of 120º with respect come the main atom because the main atom is surrounding by three regions of electron density and also according to the VSEPR theory, this electron cloud needs to be much as feasible to protect against the repulsive force.

The electron cloud developed the aircraft where the main atom(carbon) lies in the center of the triangle and other atoms space at the corner of the triangle. After, the band will arise from the central atom at angle of around 120° to each other.

The yes, really bond angles in the CH2O molecule space ∠HCH = 116 ° and ∠HCO = 122 °.


Well, we understand the polar molecule has some dipole moment because of unequal circulation of charges conversely, the non-polar molecule has actually an equal circulation of dues that reason zero dipole moment since they cancel the end each other due to the symmetrical shape of the molecule.

Is CH2O polar or non-polar? CH2O is a polar molecule because of the difference in electronegativity value in between carbon and also oxygen the creates charge imbalance and generates some dipole moment in the molecule, renders it polar in nature.

Let’s recognize why CH2O is polar in nature in detail.

Two determinants that indicate the polarity that CH2O

1. Electronegativity:

Electronegativity means the propensity of an atom come attracting electrons in the direction of itself.

If the electronegativity difference in between the atoms is high then the polarity will additionally be higher. Now, look at the electronegativity that carbon and oxygen. 

As carbon electronegativity is around 2.6 and because that oxygen, the is around 3.45. Therefore, oxygen has actually a higher tendency to attract an electron to itself 보다 carbon.

Also, the electronegativity difference between carbon and also oxygen is much more than 0.5, and also according come the Pauling range if the electronegativity difference in between atoms is higher than 0.5 climate the bond between that atom behaves together polar.

2. Dipole moment:

Dipole moment ensures the strength of polarity in between carbon and oxygen atom. As greater the dipole moment of the molecule, the an ext is the polar nature of the molecule. The electronegativity difference in between the atoms(Carbon and oxygen) induced hopeful and negative charges.

As oxygen is much more electronegative than carbon, hence, some an unfavorable charge is induced on the oxygen atom and a partial positive charge is induced ~ above the carbon atom. 

The inducing of these positive and an adverse charges generates the dipole minute directed indigenous carbon to oxygen atom due to the fact that oxygen atom is much more electronegative 보다 a carbon atom, so, that attracts an ext electrons towards itself.


The network dipole moment of formaldehyde is 2.330 D.

In mathematical terms, we can express dipole moment as D = Q×R

Dipole moment formula = charge on the atoms * the distance in between them.


Why the twin bond is formed in between carbon and oxygen atom in the CH2O lewis structure?

This is since the carbon requirements 8 electrons in its outer shell to complete the octet and attains stability, hence, for completing that octet, we converted one lone pair that oxygen atom to a solitary covalent bond.

Therefore, the bond formed between carbon and also oxygen in the CH2O lewis framework is a double covalent shortcut in nature.

Also, the official charge developed on double-bonded carbon and also oxygen atom is totally neutralized, hence, it guarantee the stability of the CH2O lewis structure.

How many shared pair or lone pair electron are current in the CH2O lewis structure?

Shared pairs electrons room the electrons the take part in the development of the chemical bond between two atoms and lone pair electrons room the electron that carry out not take part in any form of bond in between two atoms.

As per CH2O lewis structure, the carbon central atom is attached through two single bonds and also one dual bond, hence, the variety of shared pair electrons room (2 solitary bond×2 + 1 double bond ×4) = 8 mutual pair the electrons.

Also, there are only four lone pairs of electrons are present on oxygen atoms and also zero ~ above the carbon and hydrogen atoms in the CH2O lewis structure.

Why room the electron and also molecular geometry of CH2O is same?

Electron geometry predicts the geometry that a molecule through the help of lone pair as well bond pair yet molecular geometry has only taken link pair to predict the form of the molecule.

As we know, over there is no lone pair current on the central atom(carbon) in the CH2O molecule, hence, the forecast of the geometry is just done top top the communication of external inspection pair approximately the main atom.

Therefore, the both electron and also molecular geometry that CH2O is trigonal planar in nature.

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The full valence electron is easily accessible for illustration the Formaldehyde lewis structure is 12.The yes, really bond angle in the CH2O molecule room ∠HCH = 116 ° and ∠HCO = 122 °.CH2O is a polar molecule due to the fact that of the difference in electronegativity value between carbon and also oxygen the creates charge imbalance and generates part dipole moment in the molecule, renders it polar in nature.There are a complete of 4 lone bag of electrons and also 8 common pairs of electrons current in the lewis framework of CH2O.The electron geometry, and also molecular geometry the CH2O, is trigonal planar together per VSEPR theory.The network dipole moment of formaldehyde is 2.330 D.The steric number for the carbon central atom is 3, hence, the Sp2 hybridization species formed in the CH2O molecule.