A CIESE Collaborative Project

# Spring 2007 Student Reports

## Saint Eleanor School - Collegeville, PA, USA

On February 26, 2007 St. Eleanor Schools 5th grade entered the International Boiling Point Project. This is where the magic happened! This is where it all started.

Our hypothesis was that the room temperature would affect the boiling point of water. After completing our experiment, we realized that our hypothesis was wrong. Looking back over the data we collected and information from books we had in class, we learned that a better hypothesis would have been that the elevation of where the experiment took place would have had a greater impact on the boiling point temperature.

If we could change anything about this project it would be to carry out this experiment on different types of days such as: rainy, sunny, hot, and cold days. We would then be able to see if different types of conditions end with different types of results for this project.

The International Boiling Point Project was an incredible experience. We enjoyed working on this project because we learned many new things the most important was that it is alright to be wrong when forming a hypothesis. We were able to work together through the whole process: boiling water, taking and recording results, calibrating thermometers, collecting data and making graphs from all of the data. We were able to view pictures and results from other school all around the world who worked on the same experiment at the same time. Wow!

We hope that everyone involved enjoyed this project as much as we did.

## Toms River Intermediate East - Toms River , NJ, USA

Our class hypothesis was that elevation would have the greatest effect on the boiling point of water was correct.

According to the three graphs and one chart, elevation affects the boiling point of water the most as compared to volume of water, room temperature, or the heating device used. The relationship of the elevation and air pressure is a key factor of boiling point. The data indicates that as the elevation increased, the boiling point temperature decreased. The higher the elevation, the lower the air pressure. The five highest boiling points had elevations all under 500 meters. Out of the lowest 5 boiling points, two were over 1500 meters high. All of the mid-range boiling points had mid-range elevations.

When the air pressure is great, the boiling of water has a lower temperature because the gas molecules in the water can be formed much more easily that of a high-pressured elevation (low elevation). The pressure in the air enables for the bubbles and molecules to be formed in a lower temperature with less difficulty, and as a result, the boiling point becomes lower. More pressure means that the water vapor has to push harder on the air above it and less pressure means that there is less air to push out of the way. To continue, room temperature does not affect the boiling point of water because the outside temperature does not have influence to the actual water inside the container. As with the volume of water, the amount only affects the boiling time, not the boiling point temperature. The heating device is not an aspect for the boiling temperature for it is not the device that have an effect on the temperature because the device produces the same heat and is operated in identical ways for the water to boil.

A greater number of various heating sources (more bunsen burners, or alcohol lamps) is needed to truly make that aspect of the experiment valid.

A problem with the validity of some of our school's results in the boiling point averages were students lifting the thermonmeter's bulbs out the water without realizing it. We would have an observer for that next time to make sure that did not happen.

## H. H. Poole Middle School - Stafford, Virginia, United States

During the Boiling Point Experiment we learned that water doesnt always boil at the advertised temperature of 100 degrees Celsius. Our school had the lowest boiling points recorded at 91.73, 91, 94, 91, 93 and 92.5 degrees Celsius and an altitude of about 56 meters. In previous years experiments we noticed that the only temperatures the range of our 2007 data were at schools at much higher altitudes than ours. This year, schools at higher altitudes than our school had boiling points over 100 degrees Celsius. The school at 373 meters had a higher boiling point than the school at 7.62 meters.

Perhaps the use of a Bunsen Burner vs. a Hot plate influences the experimental outcome. Although everyone calibrated the thermometers in accordance with the project directions, perhaps different types of thermometers will give different readings. In any event, it is hard to reach a conclusion about altitude and the boiling point of water using Spring 2007 information because the data is all over the map. Additionally we did not have any participants reporting from very high altitudes of over 1000 meters. The highest altitude was 373 meters, so the range of altitudes is rather limited. In previous years data, with students reporting from 2100 meters, it seems that the higher altitude produced a lower boiling point than the lower altitudes.

The Spring 2007 data is inconclusive. A conclusion based upon the previous years data is that higher elevations produced lower boiling points than lower elevations. If we did this experiment again we'd like to try to standardize the amount of water used, i.e. everyone uses 250 milliliters, and the type of heat source, i.e. everyone uses hot plates by a certain manufacturer. We would also like to standardize the thermometers used, i.e. specific brands, digital or not, etc We enjoyed the experiment and thank you for giving us this opportunity!

Respectfully,
Mrs. Collins' 1st, 2nd, 5th, 6th and 7th Period Physical Science Classes

## Cresskill Jr/Sr High School - Cresskill, NJ, USA

The conclusion that was reached after examination of the given data in the International Boiling Point Project was that the boiling point of water was only affected by elevation. When considering Average Room Temperature, Volume, and Heating Device, the data fluctuated greatly and followed no recognizable trend. Of the four factors considered, only elevation was shown to directly affect the boiling point of water. A Boiling Point vs. Elevation graph shows a specific trend, which is that the higher the elevation of the boiling site, the lower the boiling point of the water.

This trend can be explained scientifically and simply, because the point where water boils is simply the point where water gains enough energy to begin to push up against air pressure and evaporate. In higher altitudes where air pressure is not as strong, it is only logical that the water will reach this point sooner, resulting in a lower boiling point.

If we ever have the chance to do this project again, we think it would be a fantastic as well as an educational idea to go to different places in the United States to see with our own eyes how elevation and air pressure affect the boiling point of water.