What is Calcium Oxide (CaO)?

Calcium oxide, frequently known as lime, is a chemical compound through the formula CaO.

Calcium oxide, additionally known together quicklime, is an alkaline substance the has remained in use because the middle ages age. That is believed that quicklime is one of the oldest chemicals recognized to the human race. It can also be described as burnt lime or lime.

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Calcium oxide has actually a tool viscosity and a high surface ar tension, to add a high to intermediate expansion and contraction rate. This product isn’t volatile at ceramic temperatures. Calcium oxide has a moderate effect on colour, except in huge amounts when it may have actually a bleaching impact on stole oxide. It additionally exists in the colour of kaki/tomato reds.

Preparation the Calcium Oxide

Calcium oxide have the right to be created by heat decomposition of products like limestone or seashells that contain calcium carbonate (CaCO3; mineral calcite) in a lime kiln.Calcium lead carbonate undergoes calcination at temperatures ranging between 1070oC-1270oC. These reactions space usually held in a rotating kiln. The assets formed together a an outcome of the reaction are burnt lime and also carbon dioxide.

The carbon dioxide that is created is immediately removed so the the reaction is preceded until the perfect of the process in accordance through Le-Chatelier’s principle.

CaCO3 → CaO + CO2

This reaction is reversible and also exothermic in nature in the front direction.

Structure of CaO Molecules

Calcium oxide molecules contain one calcium cation (which holds a charge of +2) and also one oxygen anion (which hold a fee of -2). The framework of calcium oxide is illustrated below.


Thus, it deserve to be construed that calcium oxide is an ionic link featuring one ionic bond between calcium and oxygen.

Lime Water Formula

The formula because that lime water is Ca(OH)2 and the chemical surname for lime water is calcium hydroxide. When water is added to lime calcium hydroxide Ca(OH)2 is formed according to the adhering to reaction.

CaO + H2O → Ca(OH)2

This reaction is strongly exothermic and also takes place vigorously v the formation of clouds that steam.

What is the Difference in between Quicklime and also Lime Water?

The chemistry formula the lime or quicklime is CaO. The chemical name of lime is calcium oxide. On the other hand, the chemical formula the limewater is Ca(OH)2 and also the chemical surname of this problem is calcium hydroxide.

Properties the Calcium Oxide

Quick lime is an amorphous white solid v a high melting point of 2600°It is a very stable compound and withstands high temperatures.In the visibility of water, it creates slaked lime. This process is called the slaking the lime.

CaO+H2O → Ca (OH)2

It is one oxide the is an easy in nature and also forms salts as soon as it comes in call with one acid.This link crystallizes in a cubic decision lattice.The standard molar entropy connected with calcium oxide coincides to 40 joules every mole kelvin.This link is recognized to emit an extreme glow as soon as it is heated come temperatures over 2400 levels celsius.

CaO+H2SO4 → CaSO4+H2O

CaOCalcium Oxide
Density3.34 g/cm³
Molar Mass56.0774 g/mol
SolubilitySoluble in water & glycerol
Boiling Point2,850 °C
Melting Point2,572 °C

Uses the Calcium Oxide

It is generally used for medicinal purposes and insecticides.It finds its application in the production of cement, paper, and high-grade steel.It is the cheapest alkali obtainable which is critical ingredient in the manufacturing of corrosive soda.Calcium is vital to pet life together the constituent of bones, shells, and also teeth. The most typical of the calcium compounds are calcium lead carbonate which the potter provides as a resource of calcium oxide for glazes.

Important safety and security Tips

There are few things the users have to keep in mind concerning Calcium Oxides.The reaction between quicklime and also water is typically vigorous.Quicklime can reason severe irritation, particularly when inhaled or if it comes in call with wet skin or eyes.Some that the impacts of inhalation incorporate sneezing, coughing, or laboured breathing.Additionally, it have the right to also result in abdominal pain, nausea burns with perforation that the sleep septum, and vomiting.When quicklime reacts with water it deserve to release enough heat to also ignite flammability materials.


1. Who found Calcium oxide?Ans: the was first discovered in England in 1808 when a mix of lime and also mercuric oxide to be electrolyzed by sir Humphry Davy.

2. Deserve to you drink Limewater?Ans: Lime water mimics hydrochloric mountain which is discovered in the stomach and, therefore, helps prevent constipation and also conditions such together diarrhoea.

3. Why is calcium necessary for bones?Ans: Calcium provides bones an ext brittle. Getting enough calcium in your diet not only maintains healthy bones but likewise may help prevent hypertension.

4. What room the two uses of quicklime?Ans: it is offered as a straightforward flux. That is supplied in the refining the sugar and also as a disinfectant and also germicide.

5. Go calcium oxide dissolve in water?Ans: Calcium oxide dissolves in water and glycerol.

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