A series of chemical problems with key for use in colleges and schools / by T.E. Thorpe. Rev. and enl. by W. Tate ; with a preface by H.E. Roscoe.

  • Thomas Edward Thorpe
Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: A series of chemical problems with key for use in colleges and schools / by T.E. Thorpe. Rev. and enl. by W. Tate ; with a preface by H.E. Roscoe. Source: Wellcome Collection.

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    baromctiic ])icssuie and at the level of the sea and latitude 45” weighs o'oSg^S gram. 3. The rcl. dens, of a gas is determined by :— I. W'eighing a known volume of the gas by means of;— yi. A countciTalanced globe, fdled In- the evacuation method. />’. The displacement method : a bulb of known volume containing an inert gas is kejit at a constant temperature while the experimental gas is jjassed in through one of the leading tubes in such a way as, so far as possible, to till the bulb by the disjrlacemcnt of the contained gas. C. The method of collecting in a light small flask over mercury (Bunsen). II. The effusion method (Bunsen). The rcl. dens, varies directly as the sc|uare of the time of effusion of ecpial \'olumcs. KXAMIM.K. In one of Bunsen’s experiments, a certain volume of air esca])cd under |)ressurc through a minute orifice in 1027 seconds ; under exactly similar conditions, the same volume of Cl required leyo seconds to escape through the same orilice. What is the rel. dens, of CO., (air = i) ? Rel. dens, of CO„ leyo- 16129 , , .. . ■ = ; ^ - = I7292 = Rel. Rel. dens, of air 1027- 10547 dens, of CO^. 4. The rel. dens, of a vapour is found usualh- by :— I. y1. The direct measurement of the volume of va])our ])roduced by the evaporation in an enclosed space of a known weight of the substance —the lainciple of the methods of Cay Lussac and Hofmann. />'. 'I'lic indirect measurement of the same (piantity, the volume of an inert gas displaced being actually measured —the principle of Victor Meyer’s method.