Evaporation and Intermolecular Attraction Lab

Because it is impossible to make a punny title out of that.

Materials:

• Computer
• Serial Box Interface ULI
• Data Logger
• Two Probes
• 6 Pieces of Filter Paper
• 2 Small Rubber Bands
• Methanol
• Ethanol
• 1-Propanol
• 1-Butanol
• n-Hexane
• n-Heptane

Procedure:

1. Open "Experiment 9" from the Chemistry with Computers from the experiment files of Logger Pro.
2. Wrap filter paper around the tips of both probes, and secure it with the rubber bands. 
3. Place the both probes into a container holding a sample of liquid.
4. After the probes have been in the liquids for around 30 seconds, begin data collection. Monitor the temperature for around 15 seconds to establish the initial temperature of each liquid.
5. Simultaneously remove the probes from the liquids and tape them with the tips of the probes extended of the edge of a table.
6. When both temperatures have reached minimums, stop data collection.
7. Find the maximum and minimum temperatures, then subtract them to find the change of temperature during evaporation.
8. Remove the rubber bands and discard the used filter paper.
9. Predict, using the data just collected, how the next set of liquids will react.
10. REPEAT!

Heptane (red) and Hexane (green) Test

Ethanol (red) and Methanol (green) Test

Propanol (red) and Butanol (green) Test

Data Analysis:

1. n-Heptane and 1-Butanol had nearly the same molecular weights, but had significantly different changes in temperature due to hydrogen bonds. 1-Butanol contains hydrogen bonds, but n-Heptane does not. This made it easier for n-Heptane to evaporate compared to 1-Butanol.
2. Methanol had the weakest intermolecular forces, while 1-Butanol had the strongest. We can see that methanol had the weakest bonds because of the change of temperature. Methanol changed 18.4 degrees. This shows that it had weak bonds, allowing it to evaporate more and quicker than the other liquids. 1-Butanol had the strongest bonds because its temperature did not change very much at all. It's temperature only went down by about 3.07 degrees. This means that it had stronger intermolecular forces that did not allow it to evaporate as much or as quickly as methanol. 
3. In regards of alkanes, n-Hexane had the weakest intermolecular forces, and n-Heptane had the strongest molecular forces. n-Hexane changed a total of 17 degrees, and n-Heptane changes only 9.41 degrees.
4.