Separation and identification of Group IIIA cations on the semimicro scale

13 SEPARATION AND IDENTIFICATION OF GROUP HIA CATIONS ON THE SEMIMICRO SCALE The precipitation of cations of Group IIIA 

May contain Fe(OH)3 and Mn02.xH20. Wash with a few drops of hot water or 

3 per cent H202 solution or 1 drop of saturated H2S03 solution. Warm on water bath to decompose excess H202. Divide the solution into 2 parts. 

The original solution or substanpe should be tested with K4[Fe(CN)6] or KSCN to determine whether Fe2+ or Fe3+. 

May contain [Al(OH)4] and Cr04 the latter is indicated by the yellow colour of the solution. 

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