Lessons in elementary chemistry: inorganic and organic / by Sir Henry E. Roscoe.

  • Roscoe, Henry E. (Henry Enfield), 1833-1915.
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: Lessons in elementary chemistry: inorganic and organic / by Sir Henry E. Roscoe. Source: Wellcome Collection.

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    j quickly replaced ; after the candle has burnt for three or four minutes, the vulcanised tubing is disconnected, and the glass tube allowed to hang freely. It is then seen that the weight of the apparatus is greater than it was before the candle was burnt, the pieces of caustic soda ha\ ing absorbed the sub- stances fcarbonic acid and water) produced by the combina- tion of the constituents of the taper (carbon and hydrogen) with the oxygen of the air. By the careful examination of all the known cases of chemical action it has been satisfactorily proved that a loss 2. of matter ne\xr takes place, that is iiuicslnuiible and that in chemical actions, such as that going on in the burning of the candle, a change of sl.itc and not an annihila- tion of matter occurs. The truth of this first great iirinciplc m chemical science has been gradu.illy demonstrated In- finding that the weights of the substance acting chemically upon one another always remain the same after as before the chemical changes have occurred. For determining very accurately the weight of substances, an instrument called the