Testing For Reducing Sugars Practical Flashcards
Testing for reducing sugar: 1
Label 4 boiling tubes A-D and place 4cm3 of the corresponding samples into each using a fresh syringe each time
Testing for reducing sugar: 2
Use a dropping pipette to add 2cm3 of Benedict’s reagent to each of the samples
Testing for reducing sugar: 3
Record all observations immediately
Testing for reducing sugar: 4
Place all 4 boiling tubes into the water bath
Testing for reducing sugar: 5
After 2 minutes, record observations and place back in waterbath
Testing for reducing sugar: 6
After another 2 minutes let the boiling tubes cool on a rack and record final observations and conclusions : reducing sugar would be red
PT 2 Testing for non-reducing sugar:
Label boiling tubes A-D and add 4cm3 of the corresponding samples using a fresh syringe each time
PT 2 Testing for reducing sugar: 2
Use a dropping pipette to add 2cm3 of 2mol dm-3 HCl to each sample
PT 2 Testing for reducing sugar: 3
Incubate all tubes for 2 minutes
PT 2 Testing for reducing sugar: 4
Remove tubes and Let them cool.
PT 2 Testing for reducing sugar: 5
Neutralise the acid by adding NaCO3 to each sample until no more effervescence is observed
PT 2 Testing for reducing sugar: 6
Check pH with universal indicator paper. If pH is lower than 7, continue to add NaCO3
PT 2 Testing for reducing sugar: 7
Add 2cm3 of Benedict’s reagent
PT 2 Testing for reducing sugar: 8
Incubate all boiling tubes for 2 minutes
PT 2 Testing for reducing sugar: 10
Record observations
