Science Project: The Evaporation of Fresh Water Vs. Salt Water

Beakers with measuring gauges are crucial to this research.
••• Jupiterimages/Photos.com/Getty Images

The difference between the evaporation rate of fresh and salt water makes for a simple and educational science project. If you are a student preparing a science fair project or class presentation or simply looking to further your basic scientific knowledge, conduct this experiment to demonstrate that fresh water evaporates faster than salt water.

Equipment and Materials

Assemble five identical glass beakers with measuring scales printed on the side, a weighing scale capable of measuring grams, labels and a pen to mark your beakers, a thermometer, a teaspoon, 100 g salt and a source of tap water. Furthermore, you need to find a stable environment where the atmospheric conditions will remain fairly constant, ensuring that your experiment is not exposed to any extremes of temperature or humidity. And if you are preparing a presentation or a project, use a camera to take photographs of every aspect of your experiment.

Experiment Setup

Place the five beakers next to one another on a flat surface so they receive the same light and temperature conditions. Using the scale, weigh out 10, 20, 30 and 40 g of salt, and add each amount to a different beaker. Label the beakers based on the amount of salt inside, leaving one beaker empty as your fresh water control. Add a fixed volume of tap water to each beaker, such as 125 ml, before placing the thermometer next to the five beakers. Note the temperature and time in your experiment log book, and write a small notice to place next to your experiment asking that people do not interfere with the beakers.

Procedure

Return to your beakers once a day for the duration of your experiment, which should last no less than five days. Note down the temperature, time of day and the level of water in each beaker; for consistent results, you are advised to observe your experiment at the same time everyday. Write down any other observations you might observe about the water in the beakers, such as any change of color, consistency or presence of bubbles on the surface. Take photographs of your experiment, including a clear photograph of the water level in each of the beakers.

Results

After at least five days, conclude your experiment. Draw up a line graph with one colored line representing each of the beakers. Mark the x-axis "days" and the y-axis "water volume in ml" and plot a mark on the graph once each day for each beaker based on the water level. If you are preparing a science fair project or presentation, ensure the graphs you produce are large enough that they can be viewed from up to a few feet away as this is the distance viewers will stand when looking at your science fair stall.

Related Articles

How to Calculate Evaporation Rates
Science Projects on Whether the Color of Water Affects...
Ideas for a Science Fair Project Using Kool-Aid
Two Week Science Projects
Simple Evaporation Experiments
How to Tell If it Is Humid Without a Hygrometer?
Chalk and Vinegar Science Projects
How to Make a Galilean Thermometer
Science Fair Projects About Growing Beans and the Life...
Grass Growth Science Project
Simple Science Fair Projects for 6th Graders
How to Raise the PH Level in Water
Water Evaporation Science Fair Projects
How to Measure Yeast Respiration
How to Calibrate a Refractometer
Homemade Agar Plates
Diffusion Lab Experiments
How to Make an Egg Float Using Salt for a Science Project
How to Calculate Cooling Rate
How to Build a Water Clock