Some Important Compounds Of Calcium
Chapter Name : The S- Block Elements |
Sub Topic Code : 102_11_10_10_01 |
Topic Name : Some Important Compounds Of Calcium |
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Sub Topic Name : Calcium Oxide Or Quick Lime |
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Introduction
• It is prepared on a commercial scale by heating limestone (CaCO3) in a rotary kiln at 1070-1270 K. • 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. • The addition of limited amount of water breaks the lump of lime. • 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. • It is an important primary material for manufacturing cement and is the cheapest form of alkali. • It is used in the manufacture of sodium carbonate from caustic soda. • It is employed in the purification of sugar and in the manufacture of dye stuffs.
Pre-Requisites:
Alkali earth metals, elements, periodic table
Activity:
Calcium oxide is used to make cement and for the purification of sugar.
Real Life Question:
What is the main ingredient of cement?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Quick lime | Calcium oxide. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Periodic table | Look at the elements present in the group 2 of the periodic table. |
Real life uses :
Making cement and purification of sugar.
Places to visit :
Construction site.
Practical examples around us
| Examples | Explainations |
|---|---|
| cement | Calcium oxide is the main ingredient of cement. |
What you learn in Theory:
• It is prepared on a commercial scale by heating limestone (CaCO3) in a rotary kiln at 1070-1270 K. • 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. • The addition of limited amount of water breaks the lump of lime. • 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. • It is an important primary material for manufacturing cement and is the cheapest form of alkali. • It is used in the manufacture of sodium carbonate from caustic soda. • It is employed in the purification of sugar and in the manufacture of dye stuffs.
What you learn in Practice:
• Quick lime is important for cement manufacture.