{
  "url": "https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996/schedule-2/part-I/chapter-7./paragraph-4",
  "json_url": "https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996/schedule-2/part-I/chapter-7./paragraph-4.json",
  "legislation": "nisr/1996/513",
  "legislation_title": "Fertilisers (Sampling and Analysis) Regulations (Northern Ireland) 1996",
  "legislation_url": "https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996",
  "path": "schedule/2/part/I/chapter/7./paragraph/4",
  "kind": "paragraph",
  "number": "4",
  "heading": "REAGENTS",
  "text": "4.1 Methanol.\n4.2 Sulfuric acid solution, approximately 0.05 M.\n4.3 Sodium hydroxide solution, approximately 0.1 M.\n4.4 Alkaline solution of potassium sodium tartrate:\nIn a 1 litre graduated flask dissolve 40 g of sodium hydroxide in 500 ml of water and leave to cool. Add 50 g of potassium sodium tartrate (KNaC4H4O6.4H2O). Make up to the mark and mix. Leave standing 24 hours before use.\n4.5 Copper sulfate solution:\nIn a 1 litre graduated flask dissolve 15 g of copper sulfate (CuSO4.5H2O) in 500 ml of water. Make up to the mark and mix.\n4.6 Biuret standard solution:\nIn a 250 ml graduated flask, dissolve 0.250 g of pure biuret in water. Make up to the mark and mix. 1 ml of this solution contains 0.001 g of biuret. This solution should be freshly prepared.\n4.7 Methyl red indicator solution:\nDissolve 0.1 g methyl red in 50 ml 95% ethanol and make up to 100 ml with water. Filter if necessary.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "Biuret can be purified beforehand by washing with 10% ammonia solution, then with acetone and drying under vacuum at room temperature."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/nisr/1996/513/schedule/2/part/I/chapter/7./paragraph/4",
    "retrieved_at": "2026-10-29T02:32:40.012993+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}