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    why is it important to add an equal volume of Benedict's solution to the unknown solution?
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    (Original post by Anonymousfame98)
    why is it important to add an equal volume of Benedict's solution to the unknown solution?
    Because the concentration/volume of the chemicals within the reagent isn't strong enough to react with all of the unknown solution? So you have to add an equal amount for it to fully react??

    I don't know, that's more of a chemistry question than biology although I know it's from the saccharide tests from biology.

    Ideally, an excess wants to be added, to (as Jamestg said) ensure the unknown solution (likely a reducing sugar) entirely reacts with the Copper (II) sulphate (benedict's reagent).
    I'm assuming an equal volume is a sufficient amount to allow this based upon the molar ratios in the chemical reaction (if we were to look at the equation), although using 10x more wouldn't make a difference - it'd still be in an excess and so all of the unknown solution would react (if a reducing sugar), and a precipitate would be formed. However, one may avoid this as a colour change in the solution wouldn't be particularly clear as large quantities of the blue copper sulphate would still be present.

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