Preliminary tests on non-metallic solid samples

2 PRELIMINARY TESTS ON NON-METALLIC SOLID SAMPLES 1. Appearance The appearance of the substance should be carefully noted a lens or microscope should be used if necessary. Observe whether it is crystalline or amorphous, whether it is magnetic and whether it possesses any characteristic odour or colour. 

Yellow CdS, As2S3, SnS2, Pbl2, HgO (precipitated), K4[Fe(CN)6].3H20 chromates iron(III) chloride and nitrate. 

Green Cr203, Hg2I2, Cr(OH)3 iron(II) salts, e.g. FeS04.7H20, 

Blue anhydrous cobalt salts hydrated copper(II) salts Prussian blue. 

Brown Pb02, CdO.Fe304, Ag3As04, SnS, Fe203 and Fe(OH)3 (reddish-brown). 

Pink hydrated manganese(II) and cobalt(II) salts Yellow S (if pure), CdS, AS3S3, SnS2, Pbl2, K4[Fe(CN)6], chromates, FeCl3 and Fe(N03)3 

Green Cr203, Hg2l2, Cr(OH)3, iron(II), nickel(II) and chromium(III) salts, CuCl2 -2H20, CUCO3, K2Mn04 Blue Hydrated copper(II) salts, anhydrous cobalt(II) salts, Fe4[Fe(CN)6] (Prussian blue) 

Dry tests carry out the tests described in Section 2.2, observe and evaluate results. 

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