CA(OH)2

Physical Properties of Calcium Hydroxide – Ca(OH)₂

• Appearance: Powder or small crystals
• Solubility: Slightly soluble in water (~1.7 g/L at room temperature)
• Molar Mass: 74.09 g/mol
• Melting Point: 580°C
• Density: 2.21 g/cm³

Common Applications of Calcium Hydroxide

Water and Environmental Treatment

• Widely used in water treatment plants and wastewater treatment.
• Adjusts pH, removes heavy metals, and precipitates impurities to improve water quality.
• Neutralizes acidic soils and water in environmental applications.

Construction and Building Materials

• Used in mortar, cement, and other binding materials.
• Enhances durability and water resistance of construction materials.
• Improves soil stability and reduces moisture content in construction projects.

Agriculture and Soil Improvement

• Raises soil pH and neutralizes acidity to promote plant growth.
• Eliminates harmful bacteria, fungi, and larvae in soil.
• Provides essential calcium for crops.

Food Processing and Preservation

• Used in baking, vegetable pickling, and sugar processing to clarify sugarcane juice.
• Preserves eggs and traditional foods (e.g., bánh đúc, phở).

Medical and Healthcare Applications

• Used in dental care for root canal treatment due to antibacterial properties and enamel remineralization.
• Included in some topical medications for skin infections and dermatitis.

Safety Precautions When Handling Calcium Hydroxide

Hazards:

• Excessive ingestion can cause respiratory problems, internal bleeding, paralysis, low blood pressure, increased blood pH, and organ damage.
• Dust or droplets may irritate mucous membranes, causing sneezing and coughing.
• Can saponify fats, absorb water from skin, dissolve proteins, and corrode tissues.
• Inhalation may cause chemical pneumonia.

First Aid Measures:

• Skin contact: Wash immediately with plenty of water, then neutralize with 3–5% boric acid solution.
• Eye contact: Rinse for at least 15 minutes with water or saline; 3% boric acid solution may also be used. Seek medical attention immediately.
• Inhalation: Move to a well-ventilated area away from Ca(OH)₂ dust.
• Ingestion: Drink milk or yogurt immediately; rinse mouth, then take diluted vinegar or lemon juice if conscious.

Handling:

• Always wear full personal protective equipment (gloves, goggles, protective clothing, mask) when working with calcium hydroxide.