| Iodine may be | After dilution and cooling it gives | present if the acid | a blue color with starch, paste, | be prepared from | or mucilage. | sodium nitrate | | | Hydrochloric | Free chlorine | Liberates iodine from solution acid, HCl | | of potassium iodide.  See also Molec.  Wt. 36.5 | | “Chlorides,” nitric acid. | | | Sulphuric acid | As above for nitric acid. | | | Perchloride of iron | Yellow color.  Brown precipitate | | with ammonia added till it | | smells slightly. | | Sulphuric acid, | Bisulphate of | Residue on evaporation.  H_{2}SO_{4} | potassium | Molec.  Wt. 98 | | | Sulphate of lead | Milkiness on dilution.  May be | | completely freed from lead by | | diluting with three or four times | | as much water, and allowing | | to settle. | | Acetic acid | Water | Does not solidify when cooled (glacial), | | to 17 deg.  C. (53º F.) H C_{2}H_{3}O_{2} | | Molec.  Wt. 60 | Sulphurous and | White precipitates with silver | hydrochloric | nitrate. | acids | | | | Aldehyde, or | Blackens in the light after adding | volatile tarry | silver nitrate. | matter | | | | Organic sulphuric | Smell of garlic. | acid | | | Citric acid, | Tartaric acid | Strong solution of potassium.  H_{3}C_{6} | | Acetate added to a strong solution H_{5}O_{7}H_{2}O | | of the acid will deposit white Molec.  Wt. 210 | | crystalline bitartrate. | | Pyrogallic acid | Metagallic acid | Black residue, insoluble in water.  (C_{6}H_{3})HO_{3}| | Molec.  Wt. 126 | | | | Silver nitrate, | Free nitric acid | Reddens litmus paper. (Neutral AgNO_{3} | | silver nitrate does not Molec.  Wt. 170 | | affect litmus.) | | Potassium | Chlorides and | Same as for ammonia. carbonate | sulphates | K_{2}CO_{3} | | Molec.  Wt. 138 | | | | Potassium | Potassium carbonate| A strong solution is alkaline to iodide, KI | | test paper.  Molec.  Wt. 166 | | | Sulphates and | Same as for ammonia. | chlorides | | | | Potassium iodate | A pretty strong solution becomes | | yellow from liberation of iodine