Reducing sugar colorimeter experiment. AQA watch

1. My class did the experiment where we found the absorbance of different glucose concentrations (0%, 0.5%, 1%, 2%, 5%, 10%) using a colorimeter but my results came up really mixed up and has no correlation whatsoever!
What did I do wrong?
2. (Original post by Mends)
My class did the experiment where we found the absorbance of different glucose concentrations (0%, 0.5%, 1%, 2%, 5%, 10%) using a colorimeter but my results came up really mixed up and has no correlation whatsoever!
What did I do wrong?
what axis did u plot absorbance on? did you reset the calorimeter using water each time? did you heat the reactants properly? did you use equal volumes of reactants?, your results should show a smooth curve either decreasing or increasing depending on the type of benedicts reagent you used.
3. Plotted it on the x axis, how do you reset it with water and why? i heated the solution in a 90 degrees water bath for 5 mins and i did use equal volumes

(Original post by dreamfyre)
what axis did u plot absorbance on? did you reset the calorimeter using water each time? did you heat the reactants properly? did you use equal volumes of reactants?, your results should show a smooth curve either decreasing or increasing depending on the type of benedicts reagent you used.
4. (Original post by Mends)
Plotted it on the x axis, how do you reset it with water and why? i heated the solution in a 90 degrees water bath for 5 mins and i did use equal volumes
first of all absorbance is on y axis, because independent variable which is concentration is on x - axis, secondly you reset it with water by just pressing the calibrate button - this is to reset the baseline value, i.e. 0 absorbance = as clear as water.
5. so do you put some water into a cuvette and then put it into the colorimeter then press the calibrate button and you have to do that after each solution?

(Original post by dreamfyre)
first of all absorbance is on y axis, because independent variable which is concentration is on x - axis, secondly you reset it with water by just pressing the calibrate button - this is to reset the baseline value, i.e. 0 absorbance = as clear as water.

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