give the preparation, properties and use of calcium carbonate as an antacid
Answers
Explanation:
Calcium Carbonate Uses
The list of uses of calcium carbonate is given below.
It plays an important role in construction, be it as a building material (marble) or as an ingredient in cement.
It is used in medicinal industries which manufacture antacids, tablets which are made of base materials etc.
Preparation of CaCO3
1. CaCO3 is obtained by using carbon dioxide and slaked lime as raw materials. When carbon dioxide is passed through slaked lime, calcite is obtained.
Another method to obtain calcite is by adding sodium carbonate to calcium chloride.
Ca (OH)2 + CO2 → CaCO3 + H2O
CaCl2 + Na2CO3 → CaCO3 + 2NaCl
When carbon dioxide is passed in excess it leads to the formation of calcium hydrogen-carbonate.
2. On a large scale, it is prepared by passing carbon dioxide gas through calcium hydroxide (slaked lime). However, if carbon dioxide is passed in excess, it forms the soluble calcium hydrogen-carbonate.
Ca(OH)2 + CO2→ CaCO3 + H2O
Properties of CaCO3
It is a fluffy powder.
It decomposes to give carbon dioxide when heated up to 1200K.
When it reacts with dilute acid, it liberates carbon dioxide as a by-product.
CaCO3+H2SO4 → CaSO4+H2O+CO2
At 1200K, calcium carbonate decomposes to give carbon dioxide and calcium oxide.
CaCO3 → CaO + CO2
On reacting with dilute acids, calcium carbonate gives carbon dioxide.
CaCO3 + 2HCl → CaCl2 + H2O +CO2