Bryan Kudisch
October 26, 2009
Absorbency
1.5 hours
Absorbency Inquiry
Research Question: Does the total absorptive capacity vary significantly when a particular polar
solid, in this case the cellulose of a paper towel, is soaked in a polar substance (water) as opposed to a
nonpolar substance (mineral oil)?
Background Information: Polarity is the separation of an electrical charge so that the molecule
has a dipole, or positive and negative sides. The polarity of a molecule along with other intermolecular
forces such as London dispersion forces can cause attraction between other polar molecules, but not
nonpolar molecules. Since both cellulose and water are polar, one can expect the bonds between the
compounds would be greater than with the mineral oil, a nonpolar substance. Although both substances
have some attractive forces, the higher bonding strengths of water would in turn cause the paper towel
to absorb more of it in terms of mass than of the mineral oil.
Variables:
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Independent Variable- Georgia Pacific: Acclaim paper towel
Dependant Variables- 20 grams of distilled water (polar substance) and 20 grams of mineral oil
(nonpolar substance)
Controlled Variables- Time of paper towel soaked in a substance, temperature of environment,
mass of paper towel, mass of substance paper towel is soaked in, and air pressure.
Materials:
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


Electronic Balance
80 grams of distilled water
80 grams of mineral oil
Six 250mL beakers
1 package of Georgia Pacific: Acclaim paper towels
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Tongs
Goggles
Aprons
Procedure:
1. Gather materials and put on safety equipment.
2. Measure and place approximately 20 grams of distilled water and mineral oil and into separate
250mL beakers.
3. Cut a paper towel into two .70 gram pieces.
4. Using the tongs, place a piece of paper towel into both the water and mineral oil until it is
completely soaked.
5. Use the tongs to remove the piece of paper towel from the respective beaker and let the excess
substance that is dripping off of the piece of paper towel fall back into the beaker until the
paper towel cease to drip.
6. Note the mass of substance left in the original beakers.
7. Repeat steps 2-6 twice more, until 3 trials have been performed.
8. Clean area and discard trash.
Observations:
The data recorded for the trials using distilled water are as follows:
Initial mass of distilled
water in beaker(±0.01g)
Final mass of distilled
water in beaker(±0.01g)
Percent decrease of
mass (%)
Trial 1
19.93g
Trial 2
20.31g
Trial 3
20.19g
16.67g
17.06g
16.75g
16.36%
16.00%
17.04%
Average percent of
decrease: 16.47%
The data recorded for the trials using mineral oil are as follows:
Initial mass of mineral
oil in beaker(±0.01g)
Final mass of mineral oil
in beaker(±0.01g)
Percent decrease of
mass (%)
Trial 1
20.80g
Trial 2
19.52g
Trial 3
20.02g
17.56g
16.96g
17.19g
15.58%
13.11%
14.14%
Average percent of
decrease: 14.28%
Calculations: The calculation of the percent of mass decrease was based on the following
formula:
𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒(%)
𝐷𝑖𝑓𝑓𝑒𝑟𝑒𝑛𝑐𝑒 𝑜𝑓 𝑓𝑖𝑛𝑎𝑙 𝑚𝑎𝑠𝑠 𝑎𝑛𝑑 𝑖𝑛𝑡𝑖𝑎𝑙 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑠𝑢𝑏𝑠𝑡𝑎𝑛𝑐𝑒 (𝑔)
=
𝐼𝑛𝑡𝑖𝑎𝑙 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑠𝑢𝑏𝑠𝑡𝑎𝑛𝑐𝑒 (𝑔)
Distilled Water Trials:

Trial 1- 𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =

Trial 2- 𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =

Trial 3- 𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =
19.93𝑔−16.67𝑔
= 16.36% ± .03%
19.93𝑔
20.31𝑔−17.06𝑔
= 16.00% ± .03%
20.31𝑔
20.19𝑔−16.75𝑔
= 17.04% ± .03%
20.19𝑔
Mineral Oil Trials:

Trial 1- 𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =

Trial 2- 𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =

Trial 3- 𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =
20.80𝑔−17.56𝑔
20.80𝑔
19.52𝑔−16.96𝑔
19.52𝑔
20.02𝑔−17.19𝑔
20.02𝑔
= 15.58% ±.03%
= 13.11% ±.03%
= 14.14% ±.03%
Average percent of mass decrease per substance was calculated using the following formula:
𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑝𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%)
𝑃𝑒𝑟𝑐𝑒𝑛𝑡 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 𝑜𝑓 𝑡𝑟𝑖𝑎𝑙 1(%) + 𝑝𝑒𝑟𝑐𝑒𝑛𝑡 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 𝑜𝑓 𝑡𝑟𝑖𝑎𝑙 2(%) + 𝑝𝑒𝑟𝑐𝑒𝑛𝑡 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 𝑜𝑓 𝑡𝑟𝑖𝑎𝑙 3(%)
=
𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑟𝑖𝑎𝑙𝑠
For the distilled water:
𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑝𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =
16.36%+16.00%+17.04%
3
= 16.47% ± .09%
15.58%+13.11%+14.14%
3
= 14.28% ±.09%
For the mineral oil:
𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑝𝑒𝑟𝑐𝑒𝑛𝑡 𝑜𝑓 𝑚𝑎𝑠𝑠 𝑑𝑒𝑐𝑟𝑒𝑎𝑠𝑒 (%) =
Conclusion: In this expiriment it can be noted that on average, the paper towel absorbed more
distilled water than mineral oil in terms of grams. This can be explained by the earlier statement of how
the polar forces between the cellulose in the paper towels and the water molecules in the distilled
water are stronger than the London Dispersion forces between the cellulose in the paper towels and the
mineral oil. Since the forces of attraction between the paper towel and water are strong, it allows for
more mass to be stored within the material, contrary to the forces of attraction of the paper towel and
mineral oil, since the only attractive forces between them are weak London Disperion forces, letting the
intermolecular attractions break more easily, and therefore drip off of the piece of paper towel or not
bond to it in the first place. Despite the correlation, the the equiptment used, such as the electronic
balance and its uncertainty, and the environment could have skewed the results. When dripping the
piece of paper towel, the tongs released pressure onto the soaked paper, which could have broken the
intermolecular forces and caused the paper to drip more. In the process of taking out the paper towel
from the beaker, the tongs could have also gotten wet, decreasing the mass of the remaining liquid in
the beaker. Environmentally, during the course of the expiriment the room temperature could have
varied slightly, making it easier for intermolecular forces to break as well. These random errors account
more than the slight discrepancy of the random errors because they could have actively changed the
results, such as the pressure exerted by the tongs, while the systematic errors occurred for all trials,
meaning that the percentage of decrease would not be as skewed. Another error that could jeapordize
the results is the composition of the paper towel. It is made from 95% recycled fibers, making it difficult
to distinguish just how pure the substance is of cellulose.
Improvements: Some aspects of our procedure that could have been improved include the
method of retrieving the piece of paper towel from the beaker. If we could use something that did not
excert as much pressure as the tongs but still allowed us to get it out, then there would be less of a
discrepancy. A more accurate balance could have also been used in order to reduce the uncertainty of
the data. In combating the composition of the paper towels, one could use a substance which has a
100% cellulose composition in order to minimize random errors. Lastly, in order for the mineral oil to be
more of an equal solution of its nonpolar substances, it could have been blended or stirred to use a
more similar substance for each trial.