Qualitative analysis / by William Briggs and R.W. Stewart.

  • William Briggs
Date:
1913
Catalogue details

Licence: Public Domain Mark

Credit: Qualitative analysis / by William Briggs and R.W. Stewart. Source: Wellcome Collection.

    150/180 (page 134)
    Colour of the elements:— White or grey, Reddish, Yellow, Black, C, Na, Mg, Al, K, Cr, Mn) Fe, Co, Ni, Zn, As, Ag, Cd, Sn, Sb, Ph, Bi, (Pt). Cu. [Ail). I, amorphous carbon. * Note.—Fe, Co, Ni, are distinguished from the rest as being the only elements attracted by a magnet. Malleability.—Only the elements in italics in the above list are malleable at ordinary temperatures; the rest are brittle. B. Heat the substance to dull redness in a dry test- tube.* If the substance is an element other than Ag (Au, Pt), it will either melt, volatilize, or become dull, or even burn owing to oxidation. - . Note.—(a)' Sublime and condense on cool part of tube :— S, sublimate yellowf As, I, ,, black (Iodine vapour is violet). Hg» >> grey (globules)^ (b) Melt easily:—Na, Mg, P, Iv, Zn, Cd, Sn, Jb, Fb, Bi. The first four of these take fire readily, and‘ all oxidj&e to some extent. ' \ (c) Some of the sulphides mentioned under A (c) on heating ^ in a closed tube yield a sublimate of sulphur and a little sulphur dioxide. They will, however, be better dealt with under H. C. Action of water and dilute acid. Water at the ordinary temperature is without action on any of the elements except the alkali metals Na and Kf (and the metals of the alkaline earths, Ba, Sr, Ca). If there is no action, warm the substance in a small test- * Be careful to introduce the substance so as not to soil the sides of the tube ; also do not employ large quantities of the material. t These metals may be recognized by their softness and the readiness with which they tarnish ; they should be introduced with dry fingers in very small portions into a large basin of water.