Do the Dew Point

Why do cold drinks sweat in hot weather?

Ages

8-10

Do the Dew Point

What you need: 

  • metal can with label and top removed 
  • ice cubes 
  • room-temperature water 
  • thermometer

What to do:

  1. Fill the can about halfway with room-temperature water. Make sure the outside of the can is dry.
  2. Place the thermometer in the can and record the temperature. Leave the thermometer in the can.
  3. Add a few ice cubes and stir. Carefully watch the outside of the can for "sweat" droplets to form. When they do, record the temperature. This is the dew point temperature.
  4. Try this experiment under different conditions of humidity and temperature — outside, in a steamy bathroom, etc.
  5. The dew point is the temperature at which water vapor in the air condenses to liquid. Does the dew point change under different conditions?
  From The Wow's & Why's of Weather by Mary Kay Carson
(Scholastic Professional Books)
Science & Nature Activities
Observation
Experimentation
Age 10
Age 9
Age 8
Science Experiments and Projects
Temperature
Observation