Essentials of chemistry : inorganic and organic, for the use of students in medicine / by R.A. Witthaus.

  • Witthaus, R. A. (Rudolph August), 1846-1915.
Date:
1879, ©1878
Catalogue details

Licence: Public Domain Mark

Credit: Essentials of chemistry : inorganic and organic, for the use of students in medicine / by R.A. Witthaus. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    moleculas, the proportion found to exist between the entire masses holds good between the indi- vidual molecules, and it is this proportion which ia the molecular weight desired. 48. How can we prove synthetically that the com- position of loater is H2 0 ? 1. If we make a mixture of 2 volumes of hydro- gen with 1 volume of oxygen, and pass through it an electric discharge, chemical union will take place, the gases will disappear entirely, and in their place will remain a small quantity of water. 2. If we burn hydrogen in an atmosphere of oxy- gen, and collect the result, we will find it to be water. If in No. 1 we use more than 2 volumes of hydrogen, or more than 1 volume of oxygen, the excess will remain after the union; this is in obe- dience to Dalton's first law (Q. 15). 49. What influence has temperature upon a mix- ture of oxygen and hydrogen f At the ordinary temperature a mixture of oxy- gen and hydrogen remains such indefinitely, no chemical union taking place ; but if the tempera- ture be raised, even at a single point in the mix- ture, as by applying a lighted match, or by the passage of an electric discharge, union takes place, and proceeds through the entire mass with great rapidity, causing a violent explosion. This influ- ence of temperature upon chemical action is one of great importance, and not to be lost sight of, especially in animal chemistry, as certain actions take place at the temperature of the body which are arrested when the temperature is raised or lowered a few degrees.