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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    33. Reduce the indicated BP’s given below to tein- ]ieraturcs on the hs drogen-thennoineter scale. N2O.J 2i°‘8s (;/ = 22, f = I3°'S) SiCl., 58°'20 (;/ = o) PCI3 76°-i5 (« = i8'2, t' = 26') I’OClj io7°-3o {n = o). VOCI3 i27'-i5 {n = 10, /' = 30'') CORRl-XrnON ov barometer readings. Ob.servcd barometric heights arc reduced to the height of a column of mercury at and at the level of the ; ca in latitude 45°, which would produce the same |)iessure. The corrections needed for this leduction are ; - I. Correction for temperature, due to expansion of the mercury and the material of the scale. Let m = coefficient of exj^ansion of llg, .S = co- ('flicicnt of linear expansion of the substance of the scale, h = the observed height of the barometer, and // = the or airproximately H = // li - {in-s)t\ Hence the reepured correction s)t.h. With a brass scale we have H = h (i — o‘oooi62/) and the correction is - o'oooi62.f./i; and with a glass scale similarly and the correction is -o'ooo\l’].t.h. 11. Correction for height above the sea-lc\el and lati- tude, obtained as follows :— If X be the latitude, and x the height expressed in metres of the place of observation above the sea-level, the length of the column of mercuiy which produces the standard pressure is coircctcd height ; then