Calcium formate

Calcium formate ;
Names:	calcium formate; calcium diformate; food additive Е238;
Formula:	Ca(HCOO)2;
Molar mass:	130.112 g/mol;
Density:	2.015 g/cm3;
Crystal system:	orthorhombic (α); a=10.238 Å, b=6.305 Å, c=13.456 Åα=90°, β=90°, γ=90°; tetragonal (β); a=6.776 Å, b=6.776 Å, c=9.50 Åα=90°, β=90°, γ=90°; tetragonal (δ); a=6.75 Å, b=6.75 Å, c=10.04 Åα=90°, β=90°, γ=90°;
Shapes:	https://en.crystalls.info/w/uploads/media/b/b7/Irregular_hexagonal_pedion.json Irregular hexagonal pedion ;
Color:	colorless; yellowish;
Refractive index:	1.3714 ;
Stability:	stable;
Toxicity:	non-toxic; LD50=2650mg/kg

Description

Inorganic compound, salt of bivalent earth metal calcium and organic formic acid. Doesn't form water hydrates.

Precursors

Reaction between calcium carbonate or hydroxide, and formic acid

Chemical equation:

2HCOOH + CaCO₃ = Ca(HCOO)₂ + H₂O + CO₂↑

2HCOOH + Ca(OH)₂ = Ca(HCOO)₂ + 2H₂O

For preparation of 100.00g of calcium formate а 76.92g of carbonate or 56.94g of hydroxide and 83.23g of 85%85% formic acid is required.

Add acid to the flask, then add small parts of copper compound with stirring until it will totally dissolve or, if you use carbonate, until carbon dioxide emission will stop. After reaction will stop, filter the solution and use it for crystal growing.

Storage conditions

Keep in its original form or under several layers of varnish at average humidity and room temperature. Do not keep crystals near heaters.

Solubility

TableGraph

Temperature	g/`100,00` g water	g/`100,00` g methanol	g/`100,00` g formic acid
0.8°C273.95 K <br />33.44 °F <br />493.11 °R <br />	`16.28`
15.0°C288.15 K <br />59 °F <br />518.67 °R <br />		`0.27`
15.5°C288.65 K <br />59.9 °F <br />519.57 °R <br />	`16.72`
26.3°C299.45 K <br />79.34 °F <br />539.01 °R <br />	`17.04`
30°C303.15 K <br />86 °F <br />545.67 °R <br />			`4.62`
39.7°C312.85 K <br />103.46 °F <br />563.13 °R <br />	`17.36`
56.6°C329.75 K <br />133.88 °F <br />593.55 °R <br />	`17.70`
66.6°C339.75 K <br />151.88 °F <br />611.55 °R <br />		`0.23`
76.0°C349.15 K <br />168.8 °F <br />628.47 °R <br />	`17.99`
80.5°C353.65 K <br />176.9 °F <br />636.57 °R <br />	`18.07`
100°C373.15 K <br />212 °F <br />671.67 °R <br />			`1.62`

Gallery

Growing from water solution during several weeks, using slow evaporation method. Crystals are about ~1cm in size.Calcium formate, Martinov Maxim, redditMartinov MaximReddit
Growing from water solution during several weeks, using slow evaporation method. Crystals are about ~5mm in size.Calcium formate, Martinov Maxim, redditMartinov MaximReddit
Growing from water solution during a month, using slow evaporation method. Crystal is about ~8mm in size.Calcium formate, Martinov MaximMartinov Maxim
Growing from water solution during a month, using slow evaporation method. Crystals are about ~6..8mm in size.Calcium formate, Martinov MaximMartinov Maxim
Growing from water solution during a month, using slow evaporation method. Crystals are about ~6..8mm in size.Calcium formate, Martinov MaximMartinov Maxim
Addition of urea changed the crystal shape. Growing from water solution during about a month, using slow evaporation method. Crystal is about ~1cm in length.Calcium formate, Martinov MaximMartinov Maxim
Addition of urea changed the crystal shape. Growing from water solution during about a month, using slow evaporation method. Crystal is about ~1cm in length.Calcium formate, Martinov MaximMartinov Maxim
Addition of urea changed the crystal shape. Growing from water solution during about a month, using slow evaporation method. Crystal is about ~1cm in length.Calcium formate, Martinov MaximMartinov Maxim
Addition of urea changed the crystal shape. Growing from water solution during about a month, using slow evaporation method. Crystal is about ~1cm in length.Calcium formate, Martinov MaximMartinov Maxim

Sources

Calcium compounds
Salts	Calcium acetate (Ca(CH₃COO)₂) • Calcium carbonate (CaCO₃) • Calcium formate (Ca(COOH)₂) • Calcium nitrate (Ca(NO₃)₂) • Calcium sulfate (CaSO₄) • Calcium tartrate (CaC₄H₄O₆) • Calcium trifluoroacetate (Ca(CF₃COO)₂) • Calcium chloride (CaCl₂)
Double salts	Copper-calcium acetate (CuCa(CH₃COO)₄) • Calcium-ammonium nitrate (5Ca(NO₃)₂ · NH₄NO₃)

Formates

Barium formate (Ba(COOH)₂) • Calcium formate (Ca(COOH)₂) • Cadmium formate (Cd(COOH)₂) • Copper(II) formate (Cu(COOH)₂) • Copper(II) formate and urea adduct (Cu(HCOO)₂ · 2CO(NH₂)₂) • Iron(II) formate (Fe(COOH)₂) • Iron(III) formate (Fe₂(COOH)₃) • Lead(II) formate (Pb(COOH)₂) • Manganese(II) formate (Mn(COOH)₂) • Strontium formate (Sr(COOH)₂) • Zinc formate (Zn(COOH)₂)

Calcium formate
Names:	calcium formate calcium diformate food additive Е238
Formula:	Ca(HCOO)₂
Molar mass:	130.112 g/mol
Density:	2.015 g/cm³
Crystal system:	orthorhombic (α) a=10.238 Å, b=6.305 Å, c=13.456 Åα=90°, β=90°, γ=90° tetragonal (β) a=6.776 Å, b=6.776 Å, c=9.50 Åα=90°, β=90°, γ=90° tetragonal (δ) a=6.75 Å, b=6.75 Å, c=10.04 Åα=90°, β=90°, γ=90°
Shapes:	Irregular hexagonal pedion
Color:	colorless yellowish
Refractive index:	1.3714
Stability:	stable
Toxicity:	non-toxic LD₅₀=2650mg/kg