APPENDIX
CONCENTRATION OF REAGENTS
The use of a uniform concentration of 6 2V for the acids and bases
in the desk reagent bottles has proved to be very satisfactory.
The more concentrated reagents, which are kept under the hood,
are of the full strength supplied by the manufacturers. 'Acetic add
172V, use commercial glacial acetic acid, about 99.5%, of sp. gr.
1.055.
6 2V, mix 350 cc. of glacial acetic acid with 650 cc. of water.Hydrochloric acid
12 2V, use commercial concentrated HC1 of sp. gr. 1.19.
6 2V, mix 12 2V HC1 with an equal volume of water.Nitric add
16 2V, use commercial concentrated HN0 3 of sp. gr. 1.42.
62V, mix 380 cc. of 16 2V HN0 3 with 620 cc. of water.Sulphuric add
36 N, commercial 96% H 2 SO 4 of sp. gr. 1.84.
6 2V, pour 1 volume of the 96% H2SO4 into 5 volumes of water.
Ammonium hydroxide
15 2V, use commercial concentrated NH4OH of sp. gr. 0.90.
62V, mix 400 cc. of 152V NH 4 0H with 600 cc. of water.Sodium hydroxide
62V, add to 250 grams of NaOH enough water to make the
volume 1,000 cc.Salts
12V, all salt solutions on the reagent shelves unless otherwise
labeled are understood to be 12V.
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