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

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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$778 mm. filled with gas and residual nitrogen at 77°'C. and 778 mm. 60-5274 grams. \'olumeof residual nitrogen at 9-6’ C. and 777 mm 43’4 c.c. 72. An experimental determination of the density of hydrofluoric acid under diminished ])ressure gave ;— Weight of bulb and caps in air at 19-7° C. and 772 mm 244 0120 grams. Weight of bulb and caps and vapour in air at 175° C. and 772 mm. . 244-0025 „ Cocks turned off at 3rS’ C. Bar 772-3 mm., manometer reading 106 2 mm. Weight of bulb and caps + water at 24-3’C 528-18 grams. Residual air, reduced to o'^ C. and 760 mm 3-58 c.c. „ Weight of I c.c. of air at 0° C. and 760 mm 0-0012928 „ Coefficient of cubical expansion of platinum for 1° C 0-000027 » Sp. gr. of air, // = i I4'435 Hence find the rel. dens, of the vapour of hydrofluoric acid, under the conditions at closing the cocks, as com- pared with air, and with hydrogen. 73. From the tabulated data, calculate the correspond- ing relative densities of hydrotluoric acid at the given temperatures. rc: Height of Percentage vol. of Pressure of 26-4’ B(ir. residual air. vapour. 756 mm. T-51 745 mm. 27-8 7''’3 „ 2*2 74^1 ,, 29-2’ 7(32 „ '■55 750 „ 32-0'’ 754’5 11 1-52 743 „ 331’ 770-5 2-64 750 „ 33-8’ 767 I-I.I 758 „ 3f''3' 73' 1-58 739 38-7 7^>4 » I -69 75' „$