Specifications of Hydrated Lime Calcium Hydroxide USP Grade
Calcium Hydroxide; Lime
Ca(OH)2 -- 74.09 --- CAS 1305-62-0.

Calcium Hydroxide contains not less than 95.0 percent and not more than 100.5 percent of Ca(OH)2.

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 20 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 30 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 10 mg (0.5%).
Carbonate: Mix 2 g with 50 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 20 mL of 3 N hydrochloric acid, and evaporate on a steam bath to dryness. Dissolve the residue in 20 mL of water, and filter. Dilute the filtrate with water to 40 mL, and to 20 mL of the resulting solution add 1 mL of 0.1 N hydrochloric acid, then add water to make 25 mL: the limit is 20 6g per g.
Limit of magnesium and alkali salts: Dissolve 0.50 g in a mixture of 30 mL of water and 10 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 12 mg (4.8%).

Specifications of Calcium Hydroxide BP Ph Eur Grade
Ca(OH)2 -- 74.1

DEFINITION
Content: 95.0 per cent to 100.5 per cent.

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

DESCRIPTION
Calcium Hydroxide occurs as a white powder. One gram dissolves in 630 mL of water at 25C and in 1300 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 20 mL of water, and add sufficient glacial acetic acid to effect solution. The resulting solution gives positive tests for Calcium.
Assay: Not less than 95.0% and not more than 100.5% 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 0.005%.
Lead: Not more than 2 mg/kg.
Magnesium and Alkali Salts: Not more than 4.8%.

Specifications of Calcium Hydroxide Analytical Reagent Grade
Ca(OH)2
Formula Weight 74.09
CAS Number 1305-62-0

Specifications of Calcium Hydroxide Analytical Reagent Grade
Ca(OH)2
Formula Weight 74.09
CAS Number 1305-62-0

REQUIREMENTS
Assay: 95.0% Ca(OH)2 and 3.0% CaCO3