SECT. II.]
PROPERTIES OF STEAM.
55
Liquid.
Specific
gravity.
Temperatur
Át the
beginning.
e of the water :
At the end.
n the basin.
Difference.
Boiling point.
Heat of con
version into
vapour.
Water
1-000
42°-5
49° *
6°-5
212°
942°-
Alcohol
0-825
42-
45-
3-
175
425-5
Sulphuric ether
0-7
42-
44-
2-
112
302-6
Oil of turpentine
0-888
42-
43-5
1-5
316
146-0
Petroleum
0-75
425
44-
1-5
306
1500
Nitric acid
1-494
42-
45-5
3-5
165
517-0
Ammonia
0-978
42-
47-5
5-5
140
840-0
Vinegar
1-007
42-5
48-5
6-
870-0
The quantity of water of which the specific heat would be equivalent to the
heat absorbed by the vessels, Dr. Ure has not given; but in assuming it to be
about 1660 grains, we shall be not far distant from the truth. Hence we have
32340 + 1660=34000 for the water equivalent to the specific heat of the cooling
apparatus ; and by the formula, (art. 75, note)
~ 6 5 + 49-212 = 942°, for water.
And 34( ^ x 3 + *65 (175-45) = 425°-5, for alcohol.
The others being calculated in the same manner, afford the results in the last
column, taking the specific heat from the usual tables. Through an oversight in
calculation, Dr. Ure’s numbers in the ‘ Philosophical Transactions ’ are erroneous.
82. A further correction might be applied for the quantity of steam remaining
in the retort, and the loss of heat in the operation. Dr. Ure has, in a recent cor
rection for loss of heat, made the heat of conversion of water into steam 1000 ; and
under the impression that Count Rumford’s are the most accurate experiments on
the subject, I am inclined to think this number about right. If for these sources
of loss we make a further allowance in Dr. Ure’s experiments of the specific heat of
2000 grains of water, we shall have
— (K S^ 65 +49-212 = 1007° j
and correcting the rest of the numbers in this manner, the following are obtained. 1
Liquid.
Equal
weights.
Equal
volumes.
Liquid.
Equal
weights.
Equal
volumes.
Water into steam
1007°
1007°
Petroleum into vapour
165°
124°
Alcohol into vapour
455-5
375
Nitric acid into vapour
552
830
Sulphuric ether into vapour
322-6
227
Ammonia into vapour
895
875
Oil of turpentine into vapour
161-0
143
Vinegar into vapour
930
936
1 Ure’s Dictionary of Chemistry, art. Caloric.