Calcium acetate

Calcium acetate
IUPAC name	[show] Calcium acetate
Other names	Acetate of lime Calcium ethanoate
Identifiers
Abbreviations	Ca(OAc)2
CAS number	62-54-4 Y
SMILES	[show] [Ca+2].[O-]C(=O)C.[O-]C(=O)C
InChI	[show] 1/2C2H4O2.Ca/c2*1-2(3)4;/h2*1H3,(H,3,4);/q;;+2/p-2
InChI key	VSGNNIFQASZAOI-NUQVWONBAW
ChemSpider ID	5890
Properties
Molecular formula	C4H6CaO4
Molar mass	158.17 g mol−1
Appearance	White solid hygroscopic
Density	1.6 g/cm3
Melting point	160 °C (decomposition to acetone)
Solubility in water	37.4 g/100 mL (0 °C) 34.7 g/100 mL (20 °C) 29.7 g/100 mL (100 °C)
Solubility	slightly soluble in methanol insoluble in acetone, ethanol and benzene
Acidity (pKa)	6.3-9.6
Hazards
NFPA 704	1 1 0
Autoignition temperature	680 - 730 °C
LD50	4280 mg/kg (oral, rat)
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

The chemical compound calcium acetate is the calcium salt of acetic acid. It has the formula Ca(C₂H₃O₂)₂. Its standard name is calcium acetate, while calcium ethanoate is the systematic IUPAC name. An older name is acetate of lime. The anhydrous form is very hygroscopic; therefore the monohydrate (Ca(CH₃COO)₂.H₂O, CAS [5743-26-0]) is the common form.

If an alcohol is added to a saturated solution of calcium acetate, a semisolid, flammable gel forms that is much like "canned heat" products such as Sterno.^[1] Chemistry teachers often prepare "California Snowballs", a mixture of calcium acetate solution and ethanol. The resulting gel is whitish in color, and can be formed to resemble a snowball.

Calclacite is a name for calcium acetate chloride pentahydrate, which is treated as mineral species but possess anthropogenic origin.

History

Because it is inexpensive, calcium acetate was once a common starting material for the synthesis of acetone before the development of the cumene process.^{[2] [3]}

Calcium Acetate can be prepared by soaking eggshells in vinegar. Since both reagents would have been available pre-historically, the chemical would have been observable as crystals then.

Uses

In kidney disease, blood levels of phosphate may rise (called hyperphosphatemia) leading to bone problems. Calcium acetate binds phosphate in the diet to lower blood phosphate levels. Side effects of this treatment include upset stomach.

Calcium acetate is used as a food additive, as a stabilizer, buffer and sequestrant, mainly in candy products.

References

1. ^ "Canned Heat" at Journal of Chemical Education "Chemistry comes alive!"
2. ^ Leo Frank Goodwin and Edward Tyghe Sterne (1920). "Losses Incurred in the Preparation of Acetone by the Distillation of Acetate of Lime.". Industrial & Engineering Chemistry 12 (3): 240–243. doi:10.1021/ie50123a012. 
3. ^ E. G. R. Ardagh, A. D. Bbarbour, G. E. McClellan, and E. W. McBride (1924). "Distillation of Acetate of Lime.". Industrial & Engineering Chemistry 16 (11): 1133–1139. doi:10.1021/ie50179a013.