��OUTLINES OF PHYSICAL CHEMISTRY
��Heats of Formation (in Large Calories) — continued
�� � �Gaseous
�Liquid
�Solid
�Dis- solved
�(Si, F 4 ) . .
� � � �(SiF 4 , 2HF, aq)
�(Sn, cy .
�(Sn, Cl 4 ) .
�C, Cl 4 ) . .
�from diamond .
� � �c, o, eg
� � � �(Sb 2 , S,) .
� �(B„ S,) . .
�from amorphous B
� �(Si, S 2 ) . .
�from crystallised Si
� �(C, S 2 ) . .
�from diamond .
� � �C 2 , N 2 ) . .
�id.
�-
�(C, N, H) . .
�•
�(C, N, H, 0) .
�(cyanic acid) .
�0, N, K, 0) . |
�(C, N, K, S) . |
��The numbers in this table have been obtained by various investigators, and are taken from Berthelot's ' Donn6es et lois num^riques ' (1897).
For certain very important substances, /. Thomsen has found heats of formation which do not quite agree with those given by BertheloL According to Thomsen :
(H 2 , 0) = 68-36 Cal. (for liquid water at 18°)
(C, 0) = 29-0 Cal. x mm . Q ,. . lM
)n r\ \ qa-qa p ft i (* or amorphous carbon, at lo J.
We may further quote some interesting data relating to water :
��Molecular specific heat :
from -20 to 0° (ice)
to 100° (water) at 15° 130 to 230° (steam) Molecular heat of fusion at 0°
Molecular heat of vaporisation at 0°
at 15° 100° 194°
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1-43 Cal.
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