604 PHYSIOLOGICAL CHEMISTRY 



Neutral Olive Oil. 1 Shake ordinary olive oil with a 10 per cent 

 solution of sodium carbonate, extract the mixture with ether, and 

 remove the ether by evaporation. The residue is neutral olive oil. 



Neutral Red. 1 A i per cent solution in 50 per cent alcohol. 



p-Nitrophenol. 2 A i per cent solution in 50 per. cent alcohol. 



Nylander's Reagent. 3 Digest 2 grams of bismuth subnitrate 

 and 4 grams of Rochelle salt in 100 c.c. of a 10 per cent solution 

 of potassium hydroxide. The reagent should then be cooled and 

 filtered. 



Obermayer's Reagent. 4 Add 2-4 grams of ferric chlorid to a 

 liter of hydrochloric acid (sp. gr. 1.19). 



Oxalated Plasma. 5 Allow arterial blood to run into an equal volume 

 of 0.2 per cent ammonium oxalate solution. 



Para-dimethylaminobenzaldehyde Solution. 6 This solution is made 

 by dissolving 5 grams of para-dimethylaminobenzaldehyde in 100 c.c. 

 of 10 per cent sulphuric acid. 



Para-phenylenediamine Hydrochloride Solution. 7 Two grams dis- 

 solved in 100 c.c. of water. 



Peters' Sugar Reagents. 8 (a) Copper Solution. Dissolve 34.639 

 grams of highest purity crystallized copper sulphate (such as Kahl- 

 baum's "zur analyse mit garantieschein") in water to make 500 c.c. 



(b) Alkaline Tartrate Solution. Dissolve 173 grams of sodium 

 potassium tartrate and 125 grams of potassium hydroxide in water to 

 make 500 c.c. 



(c) N/s Sodium Thiosulphate. Dissolve about 50 grams of ordinary 

 c.p. sodium thiosulphate or exactly 49.66 grams of the pure, dry, 

 recrystallized salt, in enough boiled out distilled water to make a 

 liter. Allow to stand for several days. The solution should be stan- 

 dardized against the copper solution prepared as above. For this 

 purpose introduce 20 c.c. of the copper solution into a 200 c.c. Erlen- 

 meyer flask, add 20 c.c. of strong acetic acid (30 per cent) and 40 c.c. of 

 water. Add about 7 grams of a saturated solution of KI and titrate 

 with the thiosulphate using starch as an indicator. Calculate the 

 equivalent of i c.c. of thiosulphate in Cu. One c.c. of the copper 

 sulphate solution contains 17.647 mg. of Cu. The thiosulphate remains 

 constant for some months. It should be kept in a dark bottle. 



1 Emulsification of fats, p. 180. 



2 Determination of H ion concentration, pp, 158 and 480. 



3 Nylander's test, pp. 29 and 420. 



4 Obermayer's test, p. 388. 



5 Experiments on blood plasma, p. 268. 



6 Herter's para-dimethylaminobenzaldehyde reaction, p. 219. 



7 Detection of hydrogen peroxide, p. 323. 



8 Determination of sugar, p. 525. 



