Question

Define Calcium oxide (CaO). In detail.

Answer 1

That is the Answer
Calcium oxide is a cubic crystallisation solid. Its mainly used in production of cements. It also produce heatwhen it's hydrating and form Calcium hydroxide. This reaction is also used in petroleum industry to detect water.

Answer 2

$\huge\sf{\underline{\underline{Calcium\:oxide:}}}$

$\bullet$ Calcium oxide is also known as Quick lime.

$\bullet$ It is prepared on a commercial scale by heating limestone $(CaCO_{3})$ in a rotary kiln at 1070 - 1270 K.

$\sf{CaCO_{3}}$ $\rightleftharpoons$ $\sf{Cao + CO_{2}}$

The carbon dioxide is removed as soon as it is produced to enable the reaction to proceed to completion.


Calcium oxide is a white amorphous solid. It has a melting point of 2870 K. On exposure to atmosphere, it absorbs moisture and carbon dioxide.

$\sf{CaO + H_{2}O}$ $\longrightarrow$ $\sf{Ca(OH)_{2}}$

$\sf{CaO + CO_{2}}$ $\longrightarrow$ $\sf{CaCO_{3}}$


When small amount of water is added to lime it breaks the lump, this process is called slaking of lime. Quick lime slaked with soda gives solid soda lime. Being a basic oxide, it combines with acidic oxides at high temperature.

$\sf{CaO + SiO_{2}}$ $\longrightarrow$ $\sf{CaSiO_{3}}$

$\sf{6CaO + P_{4}O_{10}}$ $\longrightarrow$ $\sf{2Ca_{3}(PO_{4})_{2}}$


$\sf{\underline{\underline{Uses\:of\:Calcium\:Oxide:}}}$

$\Rightarrow$ It is the cheapest form of alkali, it is also important primary material for manufacturing cement.

$\Rightarrow$ It is used in the manufacture of sodium carbonate from caustic soda.

$\Rightarrow$ It is used in the purification of sugar and in the manufacture of dye stuffs.