H2O is the molecular formula of water, among the major constituents the the Earth. A single molecule is comprised of 2 hydrogen atoms and one oxygen atom, which room bonded with the covalent bond. Moreover, two or more H2O molecules connect with the aid of hydrogen binding to form a compound.

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It is interesting to realize that the covalent bonds are stronger 보다 the hydrogen bonds, the is the factor why water readily reacts with the bulk of the chemical elements from the periodic table.

The Lewis structure, or likewise called an electron dot structure, is a diagrammatic depiction of identify the total variety of valence electrons existing in one atom, which are ready to undergo bond development to form a molecule and ultimately a compound.

The valence electron are displayed by illustration them together dots roughly the price of the atom, mainly in pairs.

The maximum variety of dots that can be drawn is eight per atom, together per the octet rule. Moreover, the formation of a bond since of reacting valence electrons are shown with the help of the lines.

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

It renders a single hydrogen atom to have one valence electron.

Besides this, in the case of oxygen, its digital configuration is 1s2 2s2 2p4 wherein 2p shell have the right to accommodate 6 electrons.

As over there is a dearth of 2 electrons, the total number of valence electron in an oxygen atom is six.

What room the valence electrons?

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

Moreover, if the valence electrons are unpaired, they come to be highly reactive in nature by either accepting or donating electrons to stabilize the outermost shell.

It is interesting to realize that the bigger the variety of valence electrons, the stronger will it is in the ability to expropriate the electrons.

Whereas, the smaller the variety of valence electrons, the stronger will it is in the capability of the atom come donate them.

What is the Octet rule?

According to the Octet rule, the maximum of valence electrons the an atom have the right to have is eight. Moreover, these eight electron are attracted only about the prize of the atom in the Lewis structure.

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

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

Lewis framework of H2O

The Lewis framework of hydrogen and 2 oxygen atoms mirrors a total of eight valence electrons participate in the bond development to form a solitary triatomic H2O molecule.

Here, we must understand just how the Lewis framework is attracted for the H2O molecule:

Look for the full valence electrons: it is eight to form a solitary H2O molecule.Look because that how numerous electrons are needed: it is 4 for one water (H2O) molecule according to the octet rule.Find the total variety of bonds forming: solitary covalent bonds between each oxygen and hydrogen atom.Choose a central atom: The Oxygen atom will be the main atomDraw the lewis diagram:


The Geometrical framework of the H2O molecule

The link angle among hydrogen-oxygen-hydrogen atoms (H-O-H) is 104.5°. Indigenous this, it can be taken that the geometrical framework of a single H2O molecule is bent.

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

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

According come the Lewis structure, there exists lone pair as soon as all the valence electrons roughly the atom are not paired.

Similar is a case of the oxygen atom in the H2O molecule, where 2 lone bag exist.

These lone pairs distort the bond angle as result of the lone pair-lone pair, which is an ext than the bond pair-bond pair and lone pair-bond pair repulsion.

When the lone pair increases, the bond edge decreases. As there room two lone bag on the oxygen atom, that reduces the bond angle to 104.5°.

Hybridization the H2O molecule

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

As us know, sigma (σ) bonds space the the strongest covalent bonds. Together a result, over there is high stability between the oxygen and the hydrogen atom.

It is the 2 lone pairs on the oxygen atom which makes all the difference. The hybridization the a water (H2O) molecule is sp3, whereby its oxygen has been hybridized.

According to the diagram, it can be analyzed that the solitary oxygen atom in the water (H2O) molecule has 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 bend geometry, where all at once H2O molecule mirrors 25% characteristics of s and also 75% qualities of the p orbital.

It can additional be described with the assist of a molecular orbit diagram the the H2O molecule.


The 2s orbital and also three 2p orbitals of the oxygen atom creates four brand-new hybrid orbitals which additional bonds by experience overlapping with the 1s orbit of the hydrogen atoms.

Molecular orbital diagram that water (H2O)


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

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

From the above diagram, it deserve to be seen that the six valence electrons space bonding through the 1s orbital electrons of the hydrogen atom.

The mixing and overlapping space occurring amongst the atom orbital of comparable energy.

It is taking place in such a manner that the bonding electron in lower power are developing antibonding molecular orbitals of higher energy.

The left oxygen electrons do not overlap further as result of the scarcity the electrons.

The oxygen atom has actually its electronegativity higher than hydrogen. Due to this, oxygen has actually a greater negative charge, whereas hydrogen has a confident charge. It provides oxygen attract adjacent electrons and form a bond ultimately.

On the other hand, the hydrogen does not react with adjacent molecules together it has already fulfilled the orbital and also bonded with oxygen with a sigma bond, i beg your pardon is not straightforward to break.

It leads to the formation of polarity in an H2O molecule, irrespective of having actually a network neutral charge.

You can likewise check one interesting article written around the polarity in water.


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

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It is the reason why the shortcut angle the should have actually been 109.5° is 104.5°. The hybridization the the H2O molecule is sp3 because it has actually one s orbital and three ns orbitals mix to kind four hybrid orbitals.