Page:Reflections on the Motive Power of Heat.djvu/98

From Wikisource
Jump to navigation Jump to search
This page has been validated.
76
MOTIVE POWER OF HEAT.

for all other gases; according to the theory demonstrated on page 87, the heat absorbed by these equal increases of volume is the same for all the elastic fluids, which leads to the establishment of the following proposition:

The difference between specific heat under constant pressure and specific heat under constant volume is the same for all gases.

It should be remarked here that all the gases are considered as taken under the same pressure, atmospheric pressure for example, and that the specific heats are also measured with reference to the volumes.

It is a very easy matter now for us to prepare a table of the specific heat of gases under constant volume, from the knowledge of their specific heats under constant pressure. Here is the table:

Table of the Specific Heat of Gases.
Names of Gases. Specific Heat
under
Const. Press.
Specific Heat
at
Const. Vol.
Atmospheric Air 1.000 0.700
Hydrogen Gas 0.903 0.603
Carbonic Acid 1.258 0.958
Oxygen 0.976 0.676
Nitrogen 1.000 0.700
Protoxide of Nitrogen 1.350 1.050
Olefiant Gas 1.553 1.253
Oxide of Carbon 1.034 0.734