Page:Experimental researches in chemistry and.djvu/177

162 as the quantity of oxygen which has combined with the hydrogen to form water, and which with the 0.34 of vapour nearly make the diminution of 0.9.

It will be seen at once that the oxygen required for the carbon is four times that for the hydrogen; and that the whole statement is but little different from the following theoretical one, deduced partly from the former experiments:—1 volume of vapour requires 7.5 volumes of oxygen for its combustion; 6 of the latter combine with carbon to form 6 of carbonic acid, and the 1.5 remaining combine with hydrogen to form water. The hydrogen present therefore in this compound is equivalent to 3 volumes, though condensed into one volume in union with the carbon; and of the latter elements there are present six proportionals, or 36 by weight. A volume therefore of the substance in vapour contains—

and its weight or specific gravity will be 39, hydrogen being 1. Other experiments of the same kind gave results according with these.

Among the liquid products obtained from the original fluid was one which, procured as before mentioned, by submitting to 0° the portion distilling over at 180° or 190°, corresponded with the substance already described, as to boiling-points, but differed from it in remaining fluid at low temperatures; and I was desirous of comparing the two together. I had no means of separating this body from the bicarburet of hydrogen, of which it would of course be a saturated solution at 0°. Its boiling-point was very constantly 186°. In its general characters of solubility, combustibility, action of potassium, &c., it agreed with the substance already described. Its specifc gravity was 0.86 at 60°. When raised in vapour, 1.11 grain of it gave 1.573 cubic inch of vapour at 212°, equal to 1.212 cubic inch at 60°. Hence 100 cubic inches would weigh about 91.6 grains, and its specific gravity would be 43.25 nearly. In another experiment, 1.72 grain gave 2.4 cubic inches at 212°, equal to 1.849 cubic inch at 60°; from which the weight of 100