Materials Required

Real Lab Procedure

• Take about 20 dry raisins that have intact stalks.
• Weigh the raisins on an electronic balance and note the weight.
• Pour some distilled water into a beaker.
• Transfer the raisins from the balance into the beaker.
• Allow the raisins to soak for 2-3 hours.
• Remove the swollen raisins from the water using a spatula and put them in a Petri dish containing a blotting paper.
• Gently dry the raisins using another blotting paper.
• Weigh the swollen raisins on the electronic balance and note the weight.

Simulator Procedure (as performed through the Online Labs)

You can select the measurement method by clicking on any one of the icon.

• Measure by weight
• Measure by volume

Measure by weight

• Select the sample (Raisins, Pea seeds and Gram seeds) by clicking on the required sample’s icon.
• Click and drag the sample to place it on the weighing machine.
• If you require more of the sample to weigh, you can drag it multiple times onto the weighing machine.
• Note the weight of the sample, as the initial weight (x).
• The initial weight (x) can be entered in the worksheet.
• Click and drag the weighed sample from the weighing machine and drop it into the beaker containing distilled water, to soak it.
• After the soak time is complete (the clock stops once complete), click and drag the swollen sample back onto the weighing machine to weigh it again.
• Note the weight of the swollen sample, as the final weight (y).
• The final weight (y) can be entered in the worksheet.
• Based on the values entered, the worksheet gives the percentage of water absorbed by the sample.
• You can redo the experiment by clicking on the ‘Reset’ button.

Measure by volume

• Select the sample (Raisins, Pea seeds and Gram seeds) by clicking on the required sample’s icon.
• Click, drag and drop the sample into the measuring cylinder containing 30 ml distilled water, so as to allow it to soak.
• If you require more of the sample, you can drag it and drop it into the measuring jar multiple times.
• The raise in the water level is noted as initial volume (x).
• The initial volume (x) can be entered in the worksheet.
• Click on the sample in the measuring jar and drag it back to place it in the watch glass.
• The measuring cylinder is again filled with distilled water, up to 30ml.
• Now click and drag the sample on the watch glass and drop it into the measuring jar again.
• The raise in the water level is noted as the final volume (y).
• The final volume (y) can be entered in the worksheet.
• Based on the values entered, the worksheet gives the percentage of water absorbed by the sample.
• You can redo the experiment by clicking on the ‘Reset’ button.

Observations

• The weight of dry raisins is,x… gm
• The weight of swollen raisins is, y…gm
   

Calculations

• Weight of water absorbed by the raisins =
• Percentage of water absorbed by the raisins =

Precautions

Raisins should be clean and dry and should have intact stalks.