# Fertilisers (Sampling and Analysis) Regulations (Northern Ireland) 1996, Paragraph 3: PRINCIPLE


CobaltIII combines with 1-nitroso-2-naphthol to give a red precipitate Co(C10H6ONO)3.2H2O. After the cobalt present in the extract has been brought to the cobaltIII state, the cobalt is precipitated in an acetic acid medium by a solution of 1-nitroso-2-naphthol. After filtration, the precipitate is washed and dried to constant weight and then weighed as Co(C10H6ONO)3.2H2O.

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Source: https://www.legislation.gov.uk/nisr/1996/513/schedule/2/part/I/chapter/26f./paragraph/3 (the official version)
Page: https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996/schedule-2/part-I/chapter-26f./paragraph-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.