CAS number

10043-52-4(anhydrous),10035-04-8(dihydrate)

Molecular formula

CaCl2

Appearance

White powder; hygroscopic

Odor

Odorless

Density

2.15 g/cm3 (anhydrous); 1.835 g/cm3 (dihydrate)

Boiling point

1935 °C (anhydrous)

Melting point

772 °C (anhydrous); 176 °C (dihydrate)

Acidity(pKa)

soluble in acetone, acetic acid

Solubility in H2O

74.5 g/100mL (20 °C); 59.5 g/100 mL (0 °C)

Refractive index(nD)

1.52

Solubility

soluble in acetone, acetic acid

Desiccant

Used to dry Kelp for producing sodium carbonate;

Added to liquids to remove dissolved water;

Also used in products such as DampRid and Dri-Z-Air which is advertised as an air moisture absorber;

Applied as a packaging aid to ensure dryness;

Applied to keep a liquid layer on the surface of the roadway, which holds dust down

Deicing and freezing point depression

Used particularly on road surfaces to usually prevent ice formation and to deice by depressing the freezing-point as its dissolution is exothermic, relatively harmless to plants and soil, more effective at lower temperatures than sodium chloride;

Used in solutions to prevent freezing at temperature as low as −52 °C (−62 °F), making it ideal for filling agricultural implement tires as a liquid ballast, aiding traction in cold climates

Source of calcium ions

Used to increase the hardness in swimming pools and piscines and to reduce the erosion of the concrete in the pools;

Added in marine aquariums to introduce bioavailable calcium for calcium carbonate shelled animals such as mollusks and cnidarians

Oil industry

Used to increase the density of solids free brines or to provide inhibition of swelling clays in the water phase of invert emulsion drilling fluids

Other applications

Used as an additive in plastics and in fire extinguishers, in wastewater treatment as a drainage aid, in blast furnaces as an additive to control scaffolding (clumping and adhesion of materials that prevent the furnace charge from descending), and in fabric softener as a thinner

Items

Anhydrous

Dihydrate

I

II

III

I

II

II

IV

V

VI

CaCl2(≥%)

94

92

90

77

77

74

74

72

70

Mg and Alkali-Chloride(NaCl)(%≤)

4.0

4.0

5.0

3.5

5.0

3.5

4.5

3.5

5.0

Insoluble in H2O(%≤)

0.2

0.2

0.25

0.1

0.2

0.2

0.2

0.2

0.2

Alkalinity[Ca(OH)2](%≤)

0.25

0.25

0.25

0.2

0.2

0.2

0.2

0.2

0.2

Sulfate(CaSO4)(%≤)

0.2

0.2

0.3

0.2

0.3

0.2

0.3

0.3

0.3