Odors Aloft

Source Institutions

Add to list Go to activity
Activity link broken? See if it's at the internet archive
Learners smell balloons filled with different scents to guess what's inside. From this, they infer the presence and motion of scented molecules. This is a good introduction to atoms and molecules, as well as an opportunity to talk about diffusion, states of matter, chemoreceptors and the sense of smell. For latex-sensitive learners, this activity also works with non-latex gloves. Extensions include measuring diffusion rates, and extracting essential oils from plant parts. Educator-led demonstrations include having learners act as molecules in a model of a solid, liquid, and gas, and then diffusing through a model membrane as a gas. Part of the "No Hassle Messy Science with a Wow" activity guide by OMSI, where all activities use only household materials.

Quick Guide

Preparation Time:
10 to 30 minutes

Learning Time:
10 to 30 minutes

Estimated Materials Cost:
$5 - $10 per group of students

Age Range:
Ages 4 - 14

Resource Types:
Activity, Experiment/Lab Activity, Lesson/Lesson Plan

English, Spanish

Materials List (per group of students)

  • 5-10 balloons (1 per scent used)
  • 1 permanent marker
  • 5-10 straws, pipettes, or eyedroppers
  • 1-2 teaspoons each of selection of extracts, for example: anise, almond, vanilla, coffee, lemon, chocolate, orange, banana, coconut
  • 1-2 teaspoons each of selection of spices, for example: cinnamon, curry, cloves, garlic, chili
  • 1-2 teaspoons each of other strong smelling products, for example: Vicks Vapo-Rub, baby powder, soap, perfume, lotion


  • Life Sciences
    • Human Senses and Perception
      • Smell
  • Physical Sciences
    • Chemistry
    • States of Matter
      • Solids
      • Liquids
      • Gases
      • Changes of Phase


To use this activity, learners need to:

  • smell

Learning styles supported:

  • Links STEM to other topics of interest such as arts and humanities
  • Involves hands-on or lab activities


Foreign language versions of this resource:

Components that are part of this resource:

Includes alignment to state and/or national standards:

Access Rights:

  • Free access


  • Oregon Museum of Science and Industry


  • All rights reserved, Oregon Museum of Science and Industry, 2007

Funding Sources:

  • National Science Foundation
  • Camille and Henry Dreyfus Foundation