Cao Lewis structure, characteristics: 13 must to Know Facts

CaO Lewis structure is required to illustrate for representing several knowledgeable facts regarding the compound and its formation with electronic reaction between its sub elements. There are few rules that will be mentioned in this article to impose impact of the process of structuring the Lewis structure of calcium oxide. The facts are being listed below:

CaO Lewis structure drawing

The simple steps of drawing Lewis structure are the main followed method for drawing the Lewis structure of CaO as well. Calcium oxide would be drawn with the implementation of  fundamental steps, which would  draw the structure to define the internal facts about the compound.

At first the total number of valance electron present in the compound would be identified in drawing this structure. It would help to recognise the number of electron it needs to be taken or given to each other for both calcium and oxygen.

After identifying the number of valance electron the well-suited centre atom must be identified and pout into the drawing. The other element would be put around that centre atom.

However, in the case of calcium oxide the only one oxygen and one Calcium ion take place in electron transferring process is there is no need to find out centre atom. This compound is a ionic compound.

The sketch of CaO would be completed by putting the electron dots around the elements and showing the bond pairs they are making with each other by transferring their electrons.

CaO Lewis structure resonance

Resonating structure takes place in presence of pi bond. The extra pi bond flips and switch to electrons. The resonating structure is also responsible for giving two similar kind of structure to the compounds with same chemical formula.

Calcium creates one single bond with the oxygen by transferring its two electrons. After this process the element, effectively gains 2+ charge and oxygen possesses 2- charge by accepting those two electrons. In this way the element creates one sigma bond with each other which is imposing the fact that the compound has no resonating structure at all.

CaO Lewis structure shape

The shape of any compound is easily determined from the Lewis structure. This electronic structure provides the e=information about the internal arrangement of electrons which is responsible for sketching the shape of the compound as a whole.

cao lewis structure
CaO Lewis structure from Wikipedia

CaO is ionic compound and it has impact lattice geometric and cubic shape where the positively charge Ca ions and Negatively Charged O ions get bound with each other with the help of strong electrostatic force.

CaO Lewis structure formal charge

The formal charge of ionic compounds are counted  by calculating the net remaining charge in the compound after the ions creates bonds with each other by transferrmg electrons.

In calcium oxide two electrons are transferred by calcium to the oxygen and in this way Ca becomes positively charged with 2+ ions and oxygen becomes negatively charge with 2- ions. This two opposite charge attracts each other and a compact lattice of the compound is formed. Therefore, the net charge is cancelled out in the compound.

CaO Lewis structure angle

Bond angle of compounds are easily recognised by the Lewis structures.  Lewis structure is helpful to denote the existence of lone pairs and bond pairs in the compounds.

The bond angle of CaO is 1800. As the compound is ionic and made off only two ions with one simple sigma bond.

CaO Lewis structure octet rule

Octet rule states that every element in periodic table has an urge of adopting of sharing electrons with other elements to get ultimate stability as their nearest noble element. This is why the elements seek for the electron they lack or wants to release t extra electron from their last energy level.

CaO Lewis dot in orbitals from Wikipedia

Calcium wants to release tits two excess electro from the last electronic shell and oxygen wants to adopt two electrons. Both of them target to achieve filled octet. Therefore, the electrons released by calcium are adopted by Oxygen and it makes them undergo bonding with each other.

CaO Lewis structure lone pairs

The identification of the number of lone pairs present in a compound has been managed by the Lewis structure of the compounds. The presence of lone pairs impact on the bond angle and shape of the compound as well which is clarified by VSEPR theory.

In CaO, Calcium does not hold any lone pair where oxygen hold two set of lone pairs. The l=presence of lone pairs I the compound can be predicted after completing the sketch of Lewis structure of the compound.

CaO valence electron

The number of valence electron clearly denotes the requirement of electrons in elements and indicates the reason of urging electrons.  Calculating the number of valence electrons is the fundamental step for initiating the drawing of Lewis structure of the compounds.

The number of valence electrons in Calcium is two.  Besides, the number of valence electrons present in Oxygen is six. The number of valence electrons indicates that Calcium wants to release its two electron and Oxygen wants to adopt those two electrons to fulfil octet.

CaO hybridisation

Hybridization is predicted by Lewis structure of the compounds.  As in ionic compound that is made of combination between metals and non-metals do not possesses any specific hybridization as the complete transfer of electron take place here.

For the above reason calcium oxide does not have any specific hybridisation in its cubic lattice.

CaO solubility

Solubility is also predicted by looking into the shape and geometry of the compounds. As the geometric shape of the compounds are responsible for imposing the internal attraction between the atoms and ions.

CaO is quite soluble in water and glycerol. The compound is not soluble in compounds with hydroxyl ion. The solubility of Calcium oxide in water is 1 g/840ml at 250C.

CaO ionic or covalent

The identification of Ionic and covalent compounds are managed by finding two specific properties as fundamental step. The properties are:

If the electron are completely transferred by one atom or ion to another atom or ion then it would be considered as an ionic compound.

If the electron transfer take place between one metal and one non-metal then it is considered as an ionic compound. Both the above properties are noticed in calcium oxide which denotes that the compound is totally ionic. However, other ionic properties such as high meting point, soluble in water, compact lattice geometry etc. are the properties which are ensuring the compound as ionic.

CaO acidic or basic

Basicity depends on the property of forming hydroxide by being dissolved in water.

CaO is a basic compound as it is a metal oxide. Like other metal oxide it get dissolved in water and forms Calcium Hydroxide.

CaO polar or non-polar

Ionic compounds leads to the concept of non-polarity but there are exceptions as well. It is a controversial fact about Calcium oxide, which is not reliable in exposing polarity of the compound in inorganic chemistry.

CaO is neither polar nor non-polar. It is only reliable I expressing the ionic properties. This compound has powerful internal electrostatic force between the charges. The compact structure is responsible for making the compound ionic only not polar or nonpolar.


This article has consumed an informative structure with the implementation of effective facts about the well-known chemical compound CaO. There are 13 relevant facts that have been described after sketching the Lewis electronic structure of the compound in this article.

Sarnali Mukherjee

Hi.....I am Sarnali Mukherjee, a graduate from the University of Calcutta. I love to teach and share knowledge on chemistry. I have gradually gained interest in article writing since one year ago. I would love to acquire more knowledge on my subject in the future. Let's connect through LinkedIn:

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