356 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



loOO grams of the best commercial ])arairiiie was distilled in vacuo 

 under 40 mm., and the distillates were collected at first within 10°, then 

 5°, and finally within 2°, altogether seven times. The lowest distillate 

 collected below 250°, and the final residue above 350° was only 30 

 grams. All the distillates were colorless, except the residue, which was 

 slightly brown, and nearly odorless. The distillates collected in larger 

 (jiiantities at temperatures corresponding to those of hydrocarbons 

 separated from the crude oil as follows : 



- Tricosane, a3Hi3, B. P. 25G°-258° (40 mm.). 



The distillate 25 6° -258° melted without {)urification at 48°, and the 

 melting point was not raised by crystallization from alcohol and ether. 

 Tricosane obtained by Krafft* melted at 47°. 7. Its specific gravity was 

 ascertained above its melting point. 



60° 0.7836 



70° 0.7814 



80° 0.7807 



The specific gravity of tricosane from petroleum differs materially from 

 the specific gravity of this iiydrocarbon which Kraff't obtained from the 

 ketone, lauron. 



47°. 7 0.7785 



80°.8 0.7570 



88°.8 0.7456 



A combustion of this hydrocarbon gave percentages of carbon and 

 hydrogen required for the series C„Il2„+2- 



0.1510 gram of the substance gave 0.4710 gram CO.. and 0.1989 

 gram H^O. 



Calculated for C.jHjj. Found. 



C 85.20 85.06 



H 14.80 14.73 



A determination of its molecular weight at the boiling point of benzol 

 gave a value recjuired for tricosane. 



* Ber. d. cliem. Gesollsch., 15, 1713 (1682). 



