# First Commission Directive of 26 July 1979 laying down Community methods of analysis for testing certain sugars intended for human consumption (79/796/EEC), Division 4.1: Copper II solution (Muller's solution)

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

4.1.1. Dissolve 35 g of copper II sulphate, pentahydrate (CuSO4.5H2O) in 400 ml of boiling water. Allow to cool.
4.1.2. Dissolve 173 g of sodium potassium tartrate tetrahydrate (Rochelle salt or Seignette salt; KNaC4H4O64H2O) and 68 g of anhydrous sodium carbonate in 500 ml of boiling water. Allow to cool.
4.1.3. Transfer both solutions (4.1.1 and 4.1.2) to a one litre volumetric flask and make up to one litre with water. Add 2 g of activated carbon, shake, allow to stand for several hours and filter through thick filter paper or a membrane filter.
If small amounts of copper I oxide appear during storage, the solution should be re-filtered.

---
Source: https://www.legislation.gov.uk/eudr/1979/796/annex/II/division/5/division/4/division/4.1 (the official version)
Page: https://openlegislation.uk/eu-directive-1979-796/annex-II/division-5/division-4/division-4.1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.