Copy of Does Salt Raise the Boiling Point of Water PDF

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Had to choose an experiment and prove it right or wrong. ...

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Does Salt Raise the Boiling Point of Water Mariah Smith

Introduction and Literature Review A. Cooking is almost unavoidable for most people. Even in the busiest of households, time is still made for breakfast, lunch, and dinner. When crockpot meals run out, you must dig out pots and pans and try to make a time consuming meal cook faster. Waiting for water to boil seems to take the most time. An “old wives tale” tells us to add salt to our pan of water to make it boil faster. Science tells us that salt makes it more difficult for water molecules to enter into a gas phase. This strongly suggests that by adding salt to a pot of water, the water will boil faster. Both Live Science (2016) and AstroCamp (2018) agree that salt water has a higher boiling point. Both references will aide me by supporting my project in which I have attempted to prove that adding salt to water makes the water boil faster. I compared plain water, water with added sugar, and water with added salt. Hypothesis B. I hypothesized that if salt is added to water, then the boiling point will be higher. I used a 1.5 quart pot with two cups of water in 3 tests (plain water, water with sugar, water with salt) to see if my hypothesis can be supported. C. My hypothesis that adding salt to water will cause the boiling point to be higher. This hypothesis aligns with the data collected from Live Science (2016) and AstroCamp (2018). Methods D. My independent variable was temperature. The starting temperature for the water was 76 degrees. All three trials started with a pot containing two cups of water at 76 degrees and placed on a stove top on the “high setting”. The temperature was measured once water was visibly boiling. E. My dependent variable was time (or how quickly the water reaches a boil). A stopwatch was started immediately once the pot of water was turned on to “high heat” on the stove top. Once the water was visibly boiling, the stopwatch was paused so the time in which it took the water to boil could be recorded. A stopwatch app was used to record the time. F. I controlled the amount of added variables (salt and sugar) in the two cups of water so that the amount of salt and sugar were the same and i could get an accurate and precise result. It was important to make sure that the temperature of the water, the amount of water, the heat source, the water source, and the amount of salt and sugar remain the same in order to get accurate results.

G. Materials used for this experiment included: ● 1.5 quart pot ● 2 cup measuring cup ● 1 tablespoon ● Stove top ● Meat thermometer ● Tap water ● Salt ● Sugar ● Stop watch ● Notebook to record data H. From my kitchen sink I filled a measuring cup with two cups of water and poured it into a 1.5 quart pot. I used my meat thermometer to measure the temperature of the water before placing it on the stove top and recorded the starting temperature in my notebook. I turned the stove top to “high heat” setting and started my stop watch. I left the thermometer in the water for the duration it took for it to visibly boil (constant bubbly of surface) I stopped the time and recorded it in my notebook along with the temperature of the water. I repeated this process a second time once the burner and pot that were used previously were completely cool and clean. I used the same faucet and measuring cup to measure two cups of water. Once two cups of water was in my measuring cup, I used a thermometer to measure the starting temperature of the water in order to keep my starting water temperature consistent throughout the entire experiment. Once i had two cups of water that measured 76 degrees, I poured it into the pot and add 1 tablespoon of sugar and placed it on the stove top on “high heat” and started the stopwatch. I left the thermometer in the pot until the water was visibly boiling and then recorded my time and temperature. I repeated this process a final time once the burner and pot had cooled down and was clean. I used the same faucet, made sure my starting water temperature was 76 degrees and poured it in my pot. I added 1 tablespoon of salt and then repeated the same process as before. I put the pot on the stove top on “high heat” and left the thermometer in the pot and started the stopwatch. Once the water was visibly boiling, I recorded the temperature and time it took to boil.

Results I. The plain water began with a temperature of 76 degrees and took 3 minutes and 55 seconds to boil. The boiling point was recorded at 206.5 degrees. The water with added sugar began with a starting temperature of 76 degrees and took 4 minutes and 7 seconds to boil and had a boiling point of 207 degrees. And last, the water with added salt started at 76 degrees and took 4 minutes and 41 seconds to boil with a boiling point of 210 degrees.

DATA J.

Conclusion K. My hypothesis that adding salt to water increases the boiling point was confirmed, although there wasn’t a significant difference. Before conducting this experiment, I believed that an increase in boiling point would make for a quicker boil time. I have learned that in thinking that I have contradicted myself because a higher boiling point means a longer boiling time. My overall hypothesis was confirmed. In the future, I could further my experiment to include more salt added to the water to see if the water would boil faster. L. One uncontrolled confounding variables that could have influenced my observed results would be the tap water. I am unsure of how the minerals in the water affects the boiling point and the amount of minerals in the water. There is no way to tell if there is an equal amount of minerals in each cup of water used. M. My literature review confirmed that by adding a little salt to water, that it would have a higher boiling point, though not enough to really make a difference. Both Live Science (2016) and Astrocamp (2018) agree that salt makes for a higher boiling point, but say that in cooking, it isn't a significant enough difference than using plain water. You would have to use an amount of salt that would alter the taste of the food that is being made to notice a difference.

Sources N. Greggel, Laura. “Does Salt Make Water Boil Faster?” Live Science, 22 Septemeber 2016, www.livescience.com/56214-does-salt-make-water-boil-faster.html Yarbrough, Scott. “Does Salt Water Boil Faster?” AstroCamp, 26 November 2018, www.astrocampschool.org/salt-water/...