If, for example,
the quantity of water present in a generator is more than chemically
sufficient to attack all the carbide added, however largo or small that
excess may be, no more, and, theoretically speaking, no less, acetylene
can ever be evolved than 26 parts by weight of gas for every 64 parts by
weight of calcium carbide consumed. It is, however, not correct to invert
the proposition, and to say that if the carbide is in excess of the water
added, no more, and, theoretically speaking, no less, acetylene can ever
be evolved than 26 parts by weight of gas for every 36 parts of water
consumed, as might be gathered from equation (2); because equation (1)
shows that 26 parts of acetylene may, on occasion, be produced by the
decomposition of 18 parts by weight of water. From the purely chemical
point of view this apparent anomaly is explained by the circumstance that
of the 36 parts of water present on the left-hand aide of equation (2),
only one-half, _i.e._, 18 parts by weight, are actually decomposed
into hydrogen and oxygen, the other 18 parts remaining unattacked, and
merely attaching themselves as "water of hydration" to the 56 parts of
calcium oxide in equation (1) so as to produce the 74 parts of calcium
hydroxide appearing on the right-hand side of equation (2).
Pages:
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74