Can objects float in air? Well, bubbles are so light they can sit on a layer of invisible gas and LOOK like they are floating or hovering in space! This is a nice experiment to delve into the wonders of gas density, gravity and bubbles.

Materials List

– Bowl of waterbubble mattress materials

– Crazy Bubble Juice or detergent (with a little Glycerine)

– Bubble wand

– Small fabric

– Dry Ice

– Metal Spoon



1. Bubble Juice can be slippery if spilt on the floor. Ensure you wipe up any spills immediately.

2. DRY ICE WARNING: This is very cold and can cause frost bite damage to skin if direct contact is made. An adult should be the only person using this and should be with you at all times supervising your use of this.

3. Use the metal spoon to pick up the dry ice….NOT your fingers.

Make up the bubb;e juice. The strongert the juice, the longer the bubbles will last floating on the dry ice.

bubble mattress step1

We used our Crazy Bubble Juice. You can purchase this from our online store or make your own bubble juice using dishwashing liquid and some glycerine.


Place some fabric into the bottom of a plastic or glass bowl. This will prevent the dry ice from making it too cold and vibrating the container.

Once the fabric is in place, pour in some dry ice from a plastic jug. This should make a layer / pile of dry ice on the bottom of the container.

bubble mattress step2

Wait a couple of minutes to allow the dry ice to sublime and release carbon dioxide gas into the bottom of the container.

While you are waiting use your bubble wand to practise making bubbles. Once you are ready, blow bubbles over the top of the container and some bubbles will fall into the container and float on the carbon dioxide gas.

bubble mattress step3a bubble mattress step3

Check out the ‘Wacky Science’ video of this experiment and ‘What’s Going On’ series link. They are currently ‘In Production’, so check back soon…..



Just like our experiment “Invisible Fire Extinguisher” examined the density of carbon dioxide gas, this experiment also uses this concept.

Carbon dioxide gas is heavier than air (more dense) and so creates a layer of CO2 gas inside the container.

When the bubbles are created, they are pulled dowards towards Earth due to gravity. However, as they fall into the container, they stop hitting the dry ice by landing on this heavier layer of CO2 gas. Since you can NOT see the carbob dioxide gas, it looks like they are floating in mid-air.


If you would like

– more details,

– pictures of the second half of the experiment

– information on how to investigate this further

– links to everyday examples

– management hints & teaching pointers (5P Teacher develpoment program)

 ….. then why not subscribe to one of the following


(1) Crazy science Club

Crazy Science Club slider5

(2) 5P Teacher Training course called ‘Looney Lab  Classroom Creations

Looney Lab Classroom Creations2


Or you can purchase the ‘Bright Sparkes Guide’ of this demonstration only ($2.50) which has:

    • HD pictures of experiment steps
    • Detailed explanation of science
    • Mini-challenge section (another experiment)
    • Making it a ‘Scientific Method’ experience
    • Graphing opportunities
    • REAL links and descriptions to everyday examples of concept.