It is,
however, for the correction of volumes of gases measured at different
temperatures to one (normal) temperature, and, broadly, for determining
the change of volume which a given mass of the gas will undergo with
change of temperature, that the coefficient of expansion of a gas becomes
an important factor industrially.
Ansdell has found the density of liquid acetylene to range from 0.460 at
-7 deg. C. to 0.364 at +35.8 deg. C., being 0.451 at 0 deg. C. Taking the
volume of the liquid at -7 deg. as unity, it becomes 1.264 at 35.8 deg.,
and thence Ansdell infers that the mean coefficient of expansion per degree
is 0.00489 deg. for the total range of pressure." Assuming that the liquid
was under the same pressure at the two temperatures, the coefficient of
expansion per degree Centigrade would be 0.00605, which agrees more nearly
with the figure 0.007 which is quoted, by Fouche As mentioned before, data
referring to liquid (_i.e._, liquefied) acetylene are of no practical
importance, because the substance is too dangerous to use. They are,
however, interesting in so far as they indicate the differences in
properties between acetylene converted into the liquid state by great
pressure, and acetylene dissolved in acetone under less pressure; which
differences make the solution fit for employment.
Pages:
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382