MABERY. — THE COMPOSITION OF PETROLEUM. 571 



Tetradecane, Ci 4 H 30 . 



The fraction 142°-143°, collected after the twenty -fourth distillation, 

 gave as its specific gravity, after drying over sodium, 0.7848. Alter 

 agitating with concentrated sulphuric acid, washing, and drying over 

 sodium, it gave 0.7847. After treatment with fuming sulphuric acid it 

 gave 0.7814 ; this determination, like the others, was made at 20°. 



A determination of the molecular weight of this fraction purified with 

 fuming sulphuric acid gave the following result: — 



I. 1.1049 grm. of the oil and 36.8505 grms. benzol gave a depression 

 of 0°.735. 

 II. 1.052 grm. of the oil and 35.970 grms. benzol gave a depression 

 of0°.718. 



Calculated for Found. 



C m Hjo. I. II. 



198 199.9 199.5 



A combustion gave the following percentages of carbon and hydrogen : 



0.1502 grm. of the oil gave 0.4698 grm. C0 2 and 0.2024 grm. H 2 0. 



Calculated for C 14 II 30 . Found. 



C 84.84 85.02 



H 15.16 14.96 



This specimen was purified with common concentrated acid ; another 

 portion purified with fuming sulphuric acid gave slightly different pro- 

 portions : — 



0.1458 grm. of the oil gave 0.4532 grm. C0 2 and 0.1970 grm. H 2 0. 



Calculated for C U II 30 Found. 



C 84.84 84.76 



H 15.16 15.02 



The boiling point of this fraction under 760 mm. was 236°-238°. On 

 account of decomposition when the oil is distilled in air, it is difficult to 

 determine the boiling point with great precision. 



A determination of the index of refraction of this hydrocarbon gave 

 1.4360, which corresponds to the following molecular refraction : — 



Calculated or 0,41130. Found. 



66.54 66.36 



