Exploring physical properties of water (that have biological significance).

Variables:

        Controlled variables:

• Temperature (23o)
• Amount of water on each paper (2 droplets)
• Amount of paper used (6x6 cm)
• Amount of time water is on the paper (1 minute)

Manipulated variables:

• Types of paper

• Wax
• Regular
• Paper towel
• Cardboard
• Toilet paper        

Responding variables:

• Mass of the paper before and after water absorbed

Materials:

• Wax paper
• Regular paper
• Tissue paper
• Cardboard
• Toilet paper
• Stopwatch
• Scale
• Eye-dropper
• Water
• Beakers

Procedure:

1. Measure and cut the different papers to 6x6 cm
2. Collect water in beaker, take temperature and record
3. Put first paper on scale and record weight
4. Start stopwatch while dropping 2 drops on paper
5. After 1 minute shake off paper and weight immediately – take first weight that comes
6. Repeat steps 4&5 for all papers
7. Record all data and compute the mass absorbed by the various papers

Data:

Wax paper:

Mass before water: 0.140g

Mass after water: 0.144g

Mass absorbed: 0.004g

Lined regular paper:

Mass before water: 0.205g

Mass after water: 0.238

Mass absorbed: 0.033g

Paper towel:

Mass before water: 0.168g 

Mass after water: 0.274

Mass absorbed: 0.114g

Toilet paper:

Mass before water: 0.110g

Mass after water: 0.207g

Mass absorbed: 0.117g

Cardboard:

Mass before water: 1.967g

Mass after water: 1.989g

Mass absorbed: 0.022g

Conclusion:

        My hypothesis supported our results; every piece of paper absorbed some water. It ranged from 0.004g to 0.117g. We can conclude from this that the papers not only have varied ad-hesive forces but that they are made well to do what they are meant to do. For example, the wax paper is produced for cooking, not wanting to absorb oil or any other liquid. Tissue paper is used to absorb water or liquids and our experiments proved that it does absorb the water. This proves that the water is ad-hesive to the various papers and that it is co-hesive to itself, as it did not split apart into little droplets.

Evaluation:

             We did have to re-do our lab after we tested 2 pieces of paper as we decided it would be better to keep the paper on the scale as we put the water on it so we can get an instant reading of the weight after 1 minute had passed. Some limitations that we discussed would be to maybe test a few more different papers such as wrapping paper, crepe paper and construction paper. Also we could have done the test two or three times to get more of a constant reading. A point of error that we found would after the paper towel or toilet paper as the water could still have been on the scale when we put the next piece on even though we wiped it down fast, we could have spent more time as it could have affected the weight.