Calcium bicarbonate represented by the chemical formula Ca(HCO₃)₂ or C₂H₂CaO₆ that bears the IUPAC name calcium hydrogen carbonate ^[1] is a white crystalline powder that is soluble in water ^[3]. It is an ionic compound of calcium, hydrogen, carbon, and oxygen ^{[1, 6]}. Though it is not a naturally occurring compound, it forms in the water of rivers, lakes, and streams when carbonate, bicarbonate, and calcium ions are dissolved with carbon dioxide ^[5].

Calcium Bicarbonate Identification
CAS Number	3983-19-5 [1]
PubChem CID	10176262 [1]
ChemSpider ID	8351767 [2]
UNII	7PRA4BLM2L [1]

Composition and Synthesis

Calcium bicarbonate can be prepared by a reaction between calcium carbonate and carbonic acid ^[7].

CaCO₃ + H₂CO₃ = Ca(HCO₃)₂

Properties and Characteristics of Calcium Bicarbonate

General Properties
Molar mass/molecular weight		162.11 g/mol [1]
Physical Properties
Color/appearance		White powder [1]
Melting point/freezing point		1339°C, 2442°F [3]
Boiling point		N/A [3]
Density		2.711 g cm-3 [3]
State of matter at room temperature (normal phase)		Solid [1]
Chemical Properties
Solubility in water		16.6 g/100 ml (at 20oC) [3]
pH		>7 (basic) [4]
Atomic Properties
Crystal structure	Trigonal [3]

Prominent Reactions

On heating, calcium bicarbonate decomposes to calcium carbonate, carbon dioxide and water ^[8].

Ca(HCO₃)₂ = CaCO₃ + CO₂ + H₂O

It reacts with hydrochloric acid to produce calcium chloride, carbon dioxide and water ^[9].

Ca(HCO₃)₂ + 2HCl = CaCl₂ + 2CO₂ + 2H₂O

It reacts with sulfuric acid to produce calcium sulfate, carbon dioxide and water ^[10].

Ca(HCO₃)₂ + H₂SO₄ = CaSO₄ + 2CO₂ + 2H₂O

Calcium bicarbonate reacts with nitric acid to give calcium nitrate, carbon dioxide and water ^[12].

Ca(HCO₃)₂ + 2HNO₃ = Ca(NO₃)₂ + 2CO₂ + 2H₂O

Calcium Bicarbonate Uses

1. As a food additive ^[1].
2. As an anti-caking agent ^[1].
3. As a color stabilizer ^[1].

Is It Dangerous

The compound is not harmful if ingested. However, it may cause irritation to skin, eyes and the respiratory tract on inhalation ^{[3, 5]}.

Interesting Facts

• Calcium bicarbonate causes temporary hardness of water ^[13].
• Calcium bicarbonate solution in water has health benefits due to the alkalizing effect and mineral content ^[5].

Calcium Bicarbonate (Ca(HCO₃)₂) Price

The compound costs around $200-$245 per ton. The price may vary with suppliers ^[11].

References
1. Calcium Bicarbonate – Pubchem.ncbi.nlm.nih.gov
2. Calcium Bicarbonate – Chemspider.com
3. Calcium Bicarbonate – Wikivisually.com
4. Calcium Bicarbonate – Sciencedirect.com
5. What Is Calcium Bicarbonate? – Livestrong.com
6. Why calcium bicarbonate is soluble in water while calcium calcium carbonate is insoluble? – Linkedin.com
7. How do you make calcium bicarbonate at home? – Quora.com
8. What is the balanced chemical equation for the decomposition of calcium hydrogen carbonate? – Quora.com
9. How Do I Balance calcium bicarbonate reacts with hydrochloric acid ? – Socratic.org
10. How does calcium carbonate react with sulphuric acid? – Quora.com
11. Calcium Bicarbonate Price – Alibaba.com
12. How does nitric acid react with calcium carbonate? – Quora.com
13. Calcium bicarbonate causes hardness in water but not calcium carbonate. Why – Brainly.in