# Commission Regulation (EEC) No 1764/86 of 27 May 1986 laying down minimum quality requirements for products processed from tomatoes under the production aid scheme, Division 4.5: Preparation of calibration curve

Extent: E+W+S+N.I.

Take four 10-ml volumetric flasks and pour 1 ml concentrated nitric acid and 1 ml 5 % lanthanum solution (2.3) into each.
Pour 0, 1, 3 and 5 ml respectively of a 10-ppm calclium solution into the flasks and make up to the mark with double-distilled water.
Determine the absorbance of each solution and plot the calibration curve after subtracting the blank value from the standards.

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Source: https://www.legislation.gov.uk/eur/1986/1764/annex/division/9/division/4/division/4.5 (the official version)
Page: https://openlegislation.uk/eu-regulation-1986-1764/annex/division-9/division-4/division-4.5
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.