NURSING EXAM QUESTIONS
BIOCHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Chelate to copper sulfate
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maintain pH
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Supply carbon di oxide to the solution
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As an additive
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Detailed explanation-1: -When it is dissolved in water, it gives sodium citrate and a medium almost as alkaline as the one required for the complex citrate-Cu E+ of Benedict’s solution. The ideal pH is obtained by adding more sodium bicarbonate to the aqueous solution of the complex.
Detailed explanation-2: -Preparation of Benedict’s Reagent Here, the copper(II) sulfate acts as a source of Cu2+ ions, the sodium carbonate provides an alkaline medium, and the sodium citrate forms complexes with the Cu2+ ions. Distilled water is used as a solvent.
Detailed explanation-3: -Sodium carbonate provides the alkaline conditions which are required for the redox reaction. Sodium citrate complexes with the copper (II) ions so that they do not deteriorate to copper(I) ions during storage.
Detailed explanation-4: -The sodium carbonate and sodium citrate are mixed first, and then the copper sulfate is added slowly with constant stirring. Sodium citrate acts as a complexing agent which keeps Cu2+ in solution, since it would otherwise precipitate. Sodium carbonate serves to keep the solution alkaline.