{
  "url": "https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996/schedule-2/part-I/chapter-26g./paragraph-4",
  "json_url": "https://openlegislation.uk/fertilisers-sampling-and-analysis-regulations-northern-ireland-1996/schedule-2/part-I/chapter-26g./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/26g./paragraph/4",
  "kind": "paragraph",
  "number": "4",
  "heading": "REAGENTS",
  "text": "4.1 Nitric acid (HNO3 ρ = 1.40 g/ml).\n4.2 Urea [(NH2)2 C O].\nAmmonium biflouride (NH4HF2) solution (10% w/v)\n4.3 Keep the solution in a plastic container.\nAmmonium hydroxide solution (1 + 1)\n4.4 Mix 1 volume of ammonia (NH4OH, ρ = 0.9 g/ml) with 1 volume of water.\nSodium thiosulfate standard solution\n4.5 Dissolve 7.812 g of sodium thiosulfate pentahydrate (Na2S2O3.5H2O) with water in a litre volumetric flask. This solution must be prepared so that 1 ml = 2 mg Cu. For stabilization, add several drops of chloroform. The solution must be kept in a glass container and protected from direct light.\n4.6 Potassium iodide (KI).\nPotassium thiocyanate (KSCN) solution (25% w/v)\n4.7 Keep this solution in a plastic flask.\nStarch solution (about 0.5%)\n4.8 Place 2.5 g of starch in a 600 ml beaker. Add about 500 ml of water. Boil while stirring. Cool to ambient temperature. The solution has a short preservation period. Its preservation can be extended by adding about 10 mg of mercury iodide.",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/nisr/1996/513/schedule/2/part/I/chapter/26g./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."
}