How to Make a Homemade Thermometer

Thermometer is a device or an instrument which is easily found in almost every house. It is not only used to measure the body temperature, but also to measure the temperature around us. If you are a middle school Science student who is looking for ideas for a Science project, then making a homemade thermometer can be a really interesting one. One may get the feeling that it is quite difficult but the truth is that a simple thermometer can be made from simple household materials and quite surprisingly, it provides correct reading of the environment’s temperature changes. Just like heat effects the mercury column in a clinical thermometer, the same effect can be observed in a homemade thermometer filled with another liquid such as alcohol.

Things Required:
– A Clean plastic bottle
– Clear water
– Rubbing Alcohol
– Plastic straw
– Modeling clay


  • 1

    Putting Water in a Bottle

    In the plastic bottle, pour some tap water which should be at room temperature. Do not fill more than ΒΌ of the total capacity.

  • 2

    Add Rubbing Alcohol

    Now slowly add rubbing alcohol into the bottle that you filled with water. Keep on adding until you see the that the bottle is half full.

  • 3

    Make the Liquid Visible

    To make the above prepared mixture visible like the mercury is in a clinical thermometer, add a few drops of red food color (you can use any other that might be available.)

  • 4

    Inserting Plastic Straw

    Slide a plastic straw inside the bottle and cover the opening of the bottle with the modeling clay. Make sure you adjust the straw at a level that it should not come in contact with the end of the bottle.

  • 5

    Attach Piece of Paper

    Leave the apparatus for atleast one hour to get the liquid adjusted to room temperature. Attach a piece of paper with the part of straw that is outside and above the modeling clay junction.

  • 6

    Marking the Paper

    Mark some points on a paper indicating the current temperature by taking reading from a proper thermometer or thermostat.

  • 7

    Noting the Temperature

    Place the bottle in the sun or anywhere else. As you note the reading of the bottle, there will be a rise in the liquid level which will be the same as the rise in a regular thermometer when measuring.

Leave a Reply

Your email address will not be published. Required fields are marked *

8 × = forty eight