Paper 4 · November 2004 · Enzymes

In a Benedict's test, five glucose standards from 0.001 to 0.005 mol/dm3 are each mixed with Benedict's solution and heated in a boiling water bath for 5 minutes. Which colour is expected for the HIGHEST standard, 0.005 mol/dm3?

ALight yellow

BLight orange

CDark orange

DGreen

Explanation

The Benedict's colour scale runs from green at the lowest reducing sugar concentration to a dark orange precipitate at the highest; the 0.005 mol/dm3 standard, the most concentrated, gives dark orange.

Derived from ZIMSEC Biology 9190/4 Paper 4, November 2004, Q1

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