Calcium Carbonate (CaCO₃)
Other Names
-
Limestone
-
Chalk
-
Calcite
-
Marble (natural form)
CAS Number: 471-34-1
Chemical Formula: CaCO₃
Molecular Weight: 100.09 g/mol
📘 1. Definition
Calcium Carbonate is a white, odorless, powdery or crystalline solid that occurs naturally as limestone, chalk, or marble. It is widely used as a filler, pigment, dietary supplement, and pH regulator in multiple industries. Calcium carbonate is insoluble in water but reacts with acids to release carbon dioxide. Its low cost, chemical stability, and versatility make it one of the most commonly used industrial minerals.
🧪 2. Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical Formula | CaCO₃ |
| Molecular Weight | 100.09 g/mol |
| Appearance | White powder or crystalline solid |
| Odor | Odorless |
| Density | 2.71 g/cm³ |
| Melting Point | Decomposes at 825 °C (produces CO₂) |
| Solubility | Insoluble in water; soluble in acids |
| pH | Slightly alkaline in water suspension |
| Stability | Stable under normal conditions; reacts with acids |
🧰 3. Applications / Uses
| Industry | Applications |
|---|---|
| Construction & Building | Cement, concrete, mortar, road construction |
| Plastics & Rubber | Filler to improve strength, reduce cost, and control viscosity |
| Paper & Pulp | Coating pigment, filler for brightness and opacity |
| Paints & Coatings | Pigment, extender, and opacity enhancer |
| Agriculture | Soil conditioner, liming agent to neutralize acidic soils |
| Pharmaceuticals & Food | Calcium supplement, antacid, food additive (E170) |
| Water Treatment | pH regulator, hardness remover |
| Cosmetics | Filler in powders and creams |
⚠️ 4. Safety & Handling
| Hazard | Details |
|---|---|
| Health | Low toxicity; inhalation of fine dust may irritate respiratory tract |
| Environmental | Generally safe; naturally occurring mineral |
| PPE | Dust mask, goggles, and gloves recommended when handling powders |
| Storage | Keep dry, in a cool and ventilated area |
| Handling | Avoid inhalation of dust; minimize dust generation |
📌 5. Summary
Calcium Carbonate (CaCO₃) is a versatile, low-cost mineral used as a filler, pigment, dietary supplement, and pH regulator across construction, plastics, paints, paper, agriculture, food, and cosmetics. It is chemically stable, non-toxic, and naturally abundant, but fine dust may irritate the respiratory system, so proper handling is advised.
