Easy Science Project | Change Salt Water in to Fresh Water

Are you looking for a good science project that is both fun and easy? We won third place with this interesting science experiment. In this project, you turn salt water in to fresh water within a day, teaching vaporization, evaporation and condensation. The accompanying poster can depict shipwrecked sailors in need of fresh water, making the project both educational and entertaining as well.

Pour two cups of water in to a large bowl. Add three teaspoons of table salt to the water and stir. Now, place a tea cup in the middle of the bowl of water. Make sure the water level in the bowl is below the top of the tea cup. Place plastic wrap over the bowl and secure it with a large rubber band for a nice tight seal. Place a rock or similar weight on top of the plastic, directly over the tea cup. The will enable the condensation to drip down in to the tea cup. Take a picture of your experiment before the condensation begins!

Now, carefully place your bowl in direct sunlight. Do not let the salt water to spill in to the tea cup! If it is too cold outside for evaporation to occur, bring your bowl in and place it on a heater, clothes dryer or other warm and safe source. Check your bowl the next day and take a picture of it for your presentation. If there is a lot of condensation on the plastic, gently tap the weight on top of the plastic, causing the condensation to flow downwards and in to the tea cup.

Carefully remove the plastic wrap and get ready for the taste test! First, taste the water in the large bowl. Salty! With a different spoon, taste the water in the tea cup. Amazingly, the water is fresh – not a single trace of salt!

This experiement demonstrates a few things. When you add salt (solute) to water (solvent) they become a solution. The solar (or other) heat causes the water to evaporate in to a gas. Since the salt is heavier than the water, the salt remains in the bottom of the bowl. The evaporated water then cools, turning back into its original form, resulting in condensation on top of the plastic. This fresh water then runs down the plastic and drips in to the tea cup.

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10 comments

Comments

10 Responses, Leave a Reply
  1. erick
    04 April 2010, 3:14 pm

    i want to do aproject to take an A+

    [Reply]

    amanda Reply:

    well do this one

    [Reply]

  2. amanda
    27 January 2011, 3:42 pm

    what is this project called

    [Reply]

    Katherine Reply:

    Amanda, you can call it whatever you like – the judges will love creativity. I honestly don’t remember what we called ours – I would tell you if I remembered! :) This experiment won an award and was easy to do.

    [Reply]

    Rosa Reply:

    When you did this project did you have to have a chart about it?

    [Reply]

    Katherine Reply:

    No, there was a report from what I remember. I am not sure what could have been charted, since you don’t taste it every day – there isn’t a lot to measure over a period of time. I wonder if there are saline strips that can be used carefully each day which might give enough data for a chart?

  3. Rosa
    08 February 2011, 9:00 pm

    My child are wanting to do this project for her science fair project but what I need to find out were can I get a chart on this project ?

    [Reply]

  4. Science Project Condensation
    13 September 2012, 1:12 pm

    [...] Easy Science Project | Change Salt Water In To Fresh Water …Are you looking for a good science project that is both fun and easy? We won third place with this interesting science experiment. In this project, you turn salt water in to fresh water within a day, teaching vaporization, evaporation and condensation. … Read More [...]

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    13 September 2012, 9:28 pm

    [...] Easy Science Project | Change Salt Water In To Fresh Water …We won third place with this interesting science experiment. In this project, you turn salt water in to fresh water within a day share via Reddit; Share with Stumblers; Tweet about it My child are wanting to do this project for her science fair project but what I need to … Document Viewer [...]

  6. flooded house
    18 October 2014, 5:18 pm

    It’s going to be ending of mine day, but before ending I am reading this fantastic piece of writing to improve my knowledge.

    [Reply]

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