الوصف

Specifications & Grades of Commercial Pure Hydrated Lime or Slaked Lime or Calcium Hydroxide offered

Calcium Hydroxide BP British Pharmacopoeia

Ca(OH)2 *- *4.1

DEFINITION
Content
*5.0 per cent to **0.5 per cent.

CHARACTERS
Appearance
White or almost white, fine powder.
Solubility
Practically insoluble in water.

IDENTIFICATION
A. To 0.*0 g in a mortar, add *0 ml of water R and 0.5 ml of phenolphthalein solution and mix. The suspension turns red. On addition of *7.5 ml of 1 M hydrochloric acid , the suspension becomes colourless without effervescing. The red colour occurs again when the mixture is triturated for 1 min. On addition of a further 6 ml of 1 M hydrochloric acid and triturating, the solution becomes colourless.
B. Dissolve about 0.1 g in dilute hydrochloric acid and dilute to *0 ml with water . 5 ml of the solution give reaction of calcium.

TESTS
Matter insoluble in hydrochloric acid
Maximum 0.5 per cent.
Dissolve 2.0 g in *0 ml of hydrochloric acid. Boil the solution and filter. Wash the residue with hot water. The residue weighs a maximum of *0 mg.
Carbonates
Maximum 5.0 per cent of CaCO3.
Chlorides
Maximum **0 ppm.
Sulphates
Maximum 0.4 per cent.
Arsenic
Maximum 4 ppm.
Magnesium and alkali metals
Maximum 4.0 per cent calculated as sulphates.
Heavy metals
Maximum *0 ppm.

ASSAY
To 1.**0 g in a mortar, add ****0 ml of water R and 0.5 ml of phenolphthalein solution. Titrate with 1 M hydrochloric acid by triturating the substance until the red colour disappears. The final solution is used in the tests for carbonates.
1 ml of 1 M hydrochloric acid is equivalent to *7.*5 mg of Ca(OH)2.

Calcium Hydroxide USP Ca(OH)2

Calcium Hydroxide; Lime
Ca(OH)2 *- *4.*9
Calcium hydroxide [********0].
Calcium Hydroxide contains not less than *5.0 percent and not more than **0.5 percent of Ca(OH)2.
Packaging and storage— Preserve in tight containers.
Identification—
A: When mixed with from three to four times its weight of water, it forms a smooth magma. The clear, supernatant from the magma is alkaline to litmus.
B: Mix 1 g with *0 mL of water, and add sufficient 6 N acetic acid to effect solution: the resulting solution responds to the tests for Calcium.
Limit of acid-insoluble substances— Dissolve 2.0 g in *0 mL of 4 N hydrochloric acid, and heat to boiling. Filter the mixture, wash the residue with hot water, and ignite: the weight of the residue does not exceed *0 mg (0.5%).
Carbonate— Mix 2 g with *0 mL of water: the addition of an excess of 3 N hydrochloric acid to the mixture does not cause more than a slight effervescence.
Heavy metals— Dissolve 2.0 g in *0 mL of 3 N hydrochloric acid, and evaporate on a steam bath to dryness. Dissolve the residue in *0 mL of water, and filter. Dilute the filtrate with water to *0 mL, and to *0 mL of the resulting solution add 1 mL of 0.1 N hydrochloric acid, then add water to make *5 mL: the limit is *0 6g per g.
Limit of magnesium and alkali salts— Dissolve 0.*0 g in a mixture of *0 mL of water and *0 mL of 3 N hydrochloric acid, and proceed as directed in the test for Magnesium and alkali salts under Calcium Carbonate, beginning with heat the solution, and boil for 1 minute. The weight of the residue does not exceed *2 mg (4.8%).
Assay— Transfer about 1.5 g of Calcium Hydroxide, accurately weighed, to a beaker, and gradually add *0 mL of 3 N hydrochloric acid. When the solution is dissolved, transfer it to a ***-mL volumetric flask, rinse the beaker thoroughly, adding the rinsing to the flask, dilute with water to volume, and mix. Pipette *0 mL of the solution into a suitable container, add **0 mL of water, *5 mL of 1 N sodium hydroxide, and **0 mg of hydroxy naphthol blue, and titrate with 0.*5 M edentate disodium VS to a blue endpoint. Each mL of 0.*5 M edetate disodium is equivalent to 3.**5 mg of Ca(OH)2.

Calcium Hydroxide FCC Food Grade

Slaked Lime
Calcium Hydroxide
Ca(OH)2 Formula wt *4.*0
INS: **6 CAS: [********0]

DESCRIPTION
Calcium Hydroxide occurs as a white powder. One gram dissolves in **0 mL of water at *5°, and in ***0 mL of boiling water. It is soluble in glycerin and in a saturated solution of sucrose but insoluble in alcohol.
Function: Buffer; neutralizing agent; firming agent.

REQUIREMENTS
Identification
A. Mix a sample with from 3 to 4 times its weight of water. The sample forms a smooth magma. The clear, supernatant liquid from the magma is alkaline to litmus.
B. Mix 1 g of sample with *0 mL of water, and add sufficient glacial acetic acid to effect solution. The resulting solution gives positive tests for Calcium.
Assay: Not less than *5.0% and not more than **0.5% of Ca(OH)2.
Acid-Insoluble Substances: Not more than 0.5%.
Arsenic: Not more than 3 mg/kg.
Carbonate: Passes test.
Fluoride: Not more than 0.**5%.
Lead: Not more than 2 mg/kg.
Magnesium and Alkali Salts: Not more than 4.8%.

Calcium Hydroxide ACS Analytical Reagent

Calcium Hydroxide
Ca(OH)2
Formula Wt *4.*9
CAS Number ********0

REQUIREMENTS
Assay: *5.0% Ca(OH)2  and 3.0% CaCO3

MAXIMUM ALLOWABLE 
Insoluble in hydrochloric acid: 0.*3%
Chloride (Cl): 0.*3%
Sulfur compounds (as SO4): 0.1%
Heavy metals (as Pb): 0.**3%
Iron (Fe): 0.*5%
Magnesium (Mg): 0.5%
Potassium (K): 0.*5%
Sodium (Na): 0.*5%
Strontium (Sr): 0.*5%