How does temperature change the saltiness of water? You fill three jars with water and dissolve enough salt to match ocean salinity. One jar stays at room temperature. One is heated with an aquarium heater. The third goes into the refrigerator.
After five days you measure the salinity (salt concentration) of each jar with a hydrometer. The results show how temperature shifts salt levels.
You prepare three jars of salt water and keep each at a different temperature — one at room temperature, one heated with an aquarium heater to 80 degrees Fahrenheit, and one placed in a refrigerator. After five days you use a hydrometer to measure ocean salinity and see how temperature shifts the amount of salt mixed into the water.
Ocean temperature is how warm or cold seawater is, which changes how much salt the water can hold. In this project, you fill three jars with water, dissolve enough salt to match ocean salinity, and keep each jar at a different temperature. After five days, you measure the salinity of each jar with a hydrometer to see how temperature shifts salt levels.
Method & Materials
You will prepare three jars with water and label them A, B, and C. Jar A will sit at room temperature, jar B will be heated to 80 degrees Fahrenheit, and jar C will be placed in the refrigerator. After five days, you will measure the salinity of each jar.
You will need three large jars, an aquarium heater, salt, water, a hydrometer, a refrigerator, paper, a pen or pencil, and a thermometer.
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After five days, the results showed that the salinity of the water in jar A stayed the same, the salinity of the water in jar B decreased, and the salinity of the water in jar C increased. This observation stands out because it shows that salinity decreases with an increase in temperature.
Why do this project?
This science project is interesting because it shows how temperature and salinity interact in a tangible way.
Also Consider
Experiment variations to consider include testing different temperatures and different salinities.
Full project details
Additional information and source material for this project are available below.
