Wednesday, February 29, 2012

Home-made thermometers

Are there any tricks to making the home-made thermometers work?  One of our teachers tried it here at school but cannot get the liquid to move up the straw. 

1 comment:

  1. Hi Lee-Anne,
    Thanks for your question! Make sure that you are using isopropyl alcohol as the liquid - a higher concentration of alcohol (i.e. 70% v/v) will work faster than a lower concentration (i.e. 30% v/v). Make sure that the straw is in the liquid, but not touching the bottom of the bottle. The seal between the clay and the bottle and the straw needs to be very tight. Maybe try pressing the clay down more carefully? Also, you can try holding the bottle a bit higher. Warming the air in the bottle will increase the pressure on the liquid, causing the liquid to move up the straw! Let me know how it goes :)