Exploring Moisture on the Outside of a Cold Cup

Source Institutions

Source Institutions

Add to list Go to activity
In this activity, learners explore the relationship between cooling water vapor and condensation. Learners investigate condensation forming on the outside of a cold cup. To see if the condensed water vapor comes from the air, learners use two cold cups, but limit the air around one of them by placing it in a plastic bag. Learners then compare the amount of moisture that forms on the outside of both cups. They will see that more moisture forms on the exposed cup. Learners will conclude that water vapor from the air must condense to form the moisture on the outside of a cold cup. Use this activity as a followup to "Condensation," an activity from the same resource (see related resources). [Activity is publicly available through a web crawler capture on Archive.org. Activity write-up only, images are unavailable.]

Quick Guide

Preparation Time:
5 to 10 minutes

Learning Time:
10 to 30 minutes

Estimated Materials Cost:
1 cent - $1 per group of students

Age Range:
Ages 6 - 14

Resource Types:
Activity, Experiment/Lab Activity


Materials List (per group of students)

  • Ice
  • Room-temperature water
  • 4 Clear plastic cups
  • Paper towel
  • Zip-closing plastic bag, gallon size
  • Student Activity Guide


  • Earth and Space Science
    • Earth Structure
      • Atmosphere
  • Physical Sciences
    • Heat and Thermodynamics
      • Heat and Temperature
    • States of Matter
      • Changes of Phase
  • The Nature of Science
    • The Scientific Process
      • Asking Questions
      • Conducting Investigations


To use this activity, learners need to:

  • see
  • touch

Learning styles supported:

  • Involves hands-on or lab activities


Components that are part of this resource:

Access Rights:

  • Free access


  • Kessler, James H. ; Galvan, Patricia M.


  • All rights reserved, American Chemical Society, 2007