H2O is the molecule formula the water, among the major constituents the the Earth. A single molecule is made up of two hydrogen atoms and one oxygen atom, which room bonded through the covalent bond. Moreover, two or much more H2O molecules affix with the help of hydrogen bonds to kind a compound.

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It is interesting to realize that the covalent bonds room stronger 보다 the hydrogen bonds, that is the factor why water easily reacts v the majority of the chemical aspects from the regular table.

The Lewis structure, or also called an electron period structure, is a diagrammatic depiction of determining the total number of valence electrons present in one atom, i beg your pardon are all set to experience bond development to type a molecule and ultimately a compound.

The valence electron are shown by drawing them together dots around the prize of the atom, mainly in pairs.

The maximum variety of dots that deserve to be attracted is eight per atom, together per the octet rule. Moreover, the development of a bond due to the fact that of reaction valence electrons are displayed with the aid of the lines.

The atomic number of a hydrogen atom is one, which provides its electronic configuration 1s1. As the 1s shell deserve to accommodate a preferably of two electrons, there is a dearth that one an ext electron.

It provides a single hydrogen atom to have actually one valence electron.

Besides this, in the instance of oxygen, its electronic configuration is 1s2 2s2 2p4 wherein 2p shell deserve to accommodate 6 electrons.

As over there is a dearth of two electrons, the total number of valence electrons in one oxygen atom is six.

What room the valence electrons?

The valence electrons space ‘free electrons’ current in the outermost shell of the atom. The nucleus holds the external shell weakly as it is farthest in the distance.

Moreover, if the valence electrons are unpaired, they become highly reactive in nature by one of two people accepting or donating electrons to stabilize the outermost shell.

It is interesting to realize that the bigger the number of valence electrons, the more powerful will be the ability to expropriate the electrons.

Whereas, the smaller sized the variety of valence electrons, the stronger will be the capability of the atom come donate them.

What is the Octet rule?

According to the Octet rule, the preferably of valence electrons the an atom can have is eight. Moreover, these eight electrons are drawn only around the prize of the atom in the Lewis structure.

The oxygen has actually a dearth of two valence electrons. Whereas, the 2 hydrogen atoms have actually a dearth of two valence electrons in total.

The Lewis framework of H2O is attracted in such a manner that the deficiency of each atom is fulfilled.

Lewis framework of H2O

The Lewis framework of hydrogen and also 2 oxygen atoms mirrors a complete of eight valence electrons take part in the bond development to type a single triatomic H2O molecule.

Here, we have to understand how the Lewis framework is drawn for the H2O molecule:

Look because that the full valence electrons: the is eight to type a single H2O molecule.Look for how countless electrons room needed: that is 4 for one water (H2O) molecule according to the octet rule.Find the total number of bonds forming: single covalent bonds in between each oxygen and hydrogen atom.Choose a central atom: The Oxygen atom will certainly be the central atomDraw the lewis diagram:


The Geometrical structure of the H2O molecule

The link angle among hydrogen-oxygen-hydrogen atoms (H-O-H) is 104.5°. From this, it have the right to be understood that the geometrical structure of a solitary H2O molecule is bent.

It is described with the aid of the Valence shell Electron Pair Repulsion (VSEPR) theory, which says why regardless of whether of having actually two pairs of lone electrons on the oxygen atom the bond angle is reduced to 104.5°.

The ideal bond angle for a bent-shaped molecule is 109.5°.

According to the Lewis structure, there exists lone pair when all the valence electrons approximately the atom are not paired.

Similar is a instance of the oxygen atom in the H2O molecule, where two lone bag exist.

These lone bag distort the shortcut angle as result of the lone pair-lone pair, which is more than the link pair-bond pair and lone pair-bond pair repulsion.

When the lone pair increases, the bond angle decreases. As there space two lone pairs on the oxygen atom, it reduces the bond edge to 104.5°.

Hybridization of H2O molecule

The bond between each oxygen and hydrogen atom in a water molecule is sigma (σ) through no pi (π) bonds.

As we know, sigma (σ) bonds room the the strongest covalent bonds. Together a result, there is high stability in between the oxygen and also the hydrogen atom.

It is the 2 lone bag on the oxygen atom which renders all the difference. The hybridization that a water (H2O) molecule is sp3, where its oxygen has actually been hybridized.

According come the diagram, it can be analyzed that the single oxygen atom in the water (H2O) molecule has actually one 2s orbital and three 2p orbitals. These 4 altogether leads to the formation of 4 sp3 hybridized orbitals.

It leads to the development of the tetrahedral bent geometry, where as whole H2O molecule shows 25% characteristics of s and also 75% features of the ns orbital.

It can additional be defined with the help of a molecular orbit diagram of the H2O molecule.


The 2s orbital and three 2p orbitals of the oxygen atom creates four new hybrid orbitals which more bonds by undergoing overlapping v the 1s orbital of the hydrogen atoms.

Molecular orbital diagram of water (H2O)


The molecular orbital diagram is a pictorial representation that determining chemical bonding between the molecules of a compound.

Furthermore, the molecular orbital diagram helps with determining how two sigma bonds have actually been formed and also the result of the lone bag on the structure.

From the over diagram, it can be watched that the six valence electrons room bonding with the 1s orbit electrons the the hydrogen atom.

The mixing and overlapping are occurring among the atom orbital of comparable energy.

It is occurring in together a manner that the bonding electrons in lower power are developing antibonding molecule orbitals of higher energy.

The left oxygen electrons perform not overlap further because of the scarcity that electrons.

The oxygen atom has actually its electronegativity greater than hydrogen. Because of this, oxygen has actually a greater negative charge, vice versa, hydrogen has a optimistic charge. It makes oxygen attract adjacent electrons and form a bond ultimately.

On the various other hand, the hydrogen does no react with adjacent molecules together it has already fulfilled that orbital and bonded with oxygen with a sigma bond, which is not easy to break.

It leads to the development of polarity in one H2O molecule, regardless of of having a net neutral charge.

You can likewise check one interesting post written about the polarity in water.


The Lewis framework of the triatomic H2O molecule shows two single sigma bonds in between the oxygen atom and the hydrogen atoms. Moreover, these bonds leave 2 lone bag of electron on the oxygen atom that largely contributes to the tetrahedral bending geometrical structure of the H2O molecule.

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It is the factor why the shortcut angle the should have been 109.5° is 104.5°. The hybridization that the H2O molecule is sp3 since it has one s orbital and three ns orbitals mixing to form four hybrid orbitals.