Analytical reagents : standards and tests / compiled by Edmund White.

Date:
1911
Catalogue details

Licence: In copyright

Credit: Analytical reagents : standards and tests / compiled by Edmund White. Source: Wellcome Collection.

    15/194 (page 7)
    Analytical Reagents Standards and Tests The abbreviation “Mil,” which is recognised by the Board of Trade, is used throughout to indicate a millilitre in preference to the abbreviation “ C.c.” The latter term is not strictly accurate, since a cubic centimetre is not the thousandth part of a litre of water at 15° C., the temperature at which measure-glasses are graduated. Moreover, the sound of the spoken word “Mil” is more agreeable than the two- syllable sound of “C.c.” Specific gravities at 15'5°/15'5° C. ACETIC ACID, GLACIAL. hc2h3o2. Specific gravity, 1'056; boiling-point, 119° C. Solidifies when cooled, and remains solid below 15'5° C. Contains 99'5 per cent, -acetic acid. Tests. Residue : 10 mils leave no weighable residue when evapor- ated in glass dish on a sand-bath. S ulphuric A cid : A 1 in 10 solution should show no tur- bidity after addition of barium chloride, warming, and setting aside for two hours. Sulphurous Acid: To the above liquid, if it remains clear, or to the filtrate, if a turbidity be produced, add bromine water ; no precipitate should appear on standing. Hydrochloric Acid: A 1 in 10 solution should show no oloudiness on addition of silver nitrate solution. Metals: A 1 in 20 solution must show no precipitate or turbidity on addition of an equal volume of hydrogen sulphide solution; or on neutralisation with ammonia and addition of ammonium sulphide solution. Empyreumatic Substances: Foreign organic substances may be detected by their reducing action on permanganate,