The numbers correspond to an amplitude of 10 centimetres and a period of two seconds.
Now taking the isomers H 3 C CC1 3 (M„ = 108) and C1H 2 C CHC1 2 (M„ = we see the negative chlorine atoms heaped up in the left hand formula, but distributed in the second; the former therefore may be presumed to occupy a larger space, the molecular volume, that is, the volume in cubic centimetres occupied by the molecular weight in grams, actually being 108 in the former, and 103 in the latter case (compare Chemistry: Physical).
We have then 11=Io(1 j) I =I 1(1j) =Io(1 j)2 1 3 =1 2 (1 - j) =Io(11)3 and so on, so that if I is the intensity after passing through a thickness t in centimetres I = Io(1 We might call j, which is the proportion absorbed in one centimetre, the "coefficient of absorption" of the medium.
The pure acid (too% H2S04) cannot be prepared by boiling down a weaker acid under any pressure (at least between 3 and 300 centimetres of mercury), an acid of the composition H 2 SO 411 1 2 H 2 O or 12S03,13H20 being invariably obtained.
By the action of the aluminium-mercury couple and water), but better, according to C. Goldschmidt (Ber., 1896, 29, p. 2307) by dissolving nitrobenzene in ten times its weight of ether containing a few cubic centimetres of water, and heating with excess of zinc dust and anhydrous calcium chloride for three hours on a water bath.