Quantitative Glucose Test

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LAB 2:
DATE: 29TH September, 2011.
SUBJECT: Biology
TITLE: Quantitative Glucose Test
AIM: To determine the amount of glucose in three unknown samples namely A, B and C
Biological molecules are held together by covalent bonds, hydrogen bonds among others bonds in various ways to produce large molecules called macromolecules. Simple organic compounds and macromolecules molecules vary in structure and can be distinguished by their functional groups. Molecules of a certain class have similar chemical properties because they have the same functional group. A chemical test that is sensitive to that group can be used to identify molecules that are in that class. There are also tests which measure the quantity of
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In the results we can see that the purple pink solution of potassium permanganate (MnO4-) was reduced to a colourless solution of manganese ions (Mn2+).
MnO4- + 8H+ + 5e-  Mn2+ + 4H2O
From purple pink, to a colourless solution. As a result of this reaction the glucose is oxidised. Potassium permanganate is used as a qualitative test for the presence of double or triple bonds in a molecule, since the reaction decolourises the permanganate solution. Glucose (C6H12O6) is a monosaccharide reducing sugar. In this reaction the glucose readily donates electrons which are accepted by the permanganate causing it to change colour. The time taken for the loss of colour from a standardised solution of permanganate is directly related to the concentration of glucose present in solution.
In order for the experiment to be balanced there were three types of variables that need to be taken into consideration. These are the independent variables, dependant variables and the fixed variables. Independent variables such as the reducing sugars used were measured accurately and the same amount of each were put into each boiling tube also the
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