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17 Cards in this Set
- Front
- Back
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Step 1 |
Label 5 test tubes of glucose solutions with their known concentrations. |
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Step 2 |
Add 5cm3 of Benedict's Reagent to each tube |
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Step 3 |
Add 2cm3 of each solution to the appropriately labeled test tube |
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Step 4 |
Stir each solution with a clean, dry glass rod |
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Step 5 |
Place all test tubes in a water bath at 80 degrees c for 10 mins, then remove. |
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Step 6 |
Once cooled, filter the contents of each tube through a funnel into a new test tube labeled with the concentration. |
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Step 7 |
Use the calorimeter to find absorbance or transmission. |
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Step 8 |
Draw a table to place the results in and draw a graph for them. |
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Step 9 |
Put 2cm3 of the solution with unknown glucose concentration in a test tube and add 5cm3 of Benedict's Reagent |
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Step 10 |
Put in a waterbath for 10 minutes at 80 degrees c |
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Step 11 |
Filter contents and put in a calorimeter |
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Step 12 |
Plot on the graph and use this to determine glucose concentration. |
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What is absorbance? |
The amount of light absorbed by a solution. The darker the solution, the higher the absorbance. |
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What is transmission? |
The amount of light which passes through the solution. The darker the solution, the lower the transmission. |
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What are the units for absorbance and transmission? |
AU |
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Why might this test not be accurate? |
Because, other reducing sugars, like fructose, also give a positive result with Benedict's reagent which would affect the results. |
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What can we keep the same in the test? |
The volume and concentration of Benedict's reagent. The volume of glucose used. |
