Liquid Nitrogen Smoke Cloud!

Among my favorite new pieces of science equipment are my liquid nitrogen dewars. A dewar is a special container designed to store liquefied gases. It is like a special thermos but much larger. When you have a dewar and are trained in safely handling one, you can do science experiments with liquid nitrogen.

Liquid nitrogen is a super cold liquid version of nitrogen. It is so cold that is boils at −320 °F. That is 352 degrees colder than the temperature that makes water freeze. And it is even colder when it is still a liquid! That’s cold!

My first dewar after filled for the very first time! It weighs over 100 pounds filled and is being loaded into the Yuckmobile with a forklift!
My second dewar is the one I use for shows. It is much smaller an has a blue wrap. My sometimes co-host Luke is shown with it here!

One of my favorite demonstrations with liquid nitrogen is making a ‘smoke cloud.’ The smoke is actually a nitrogen being released as a vapor. In this demonstration, you poor warm water into a container of liquid nitrogen. The extreme temperature change causes the nitrogen to turn into a vapor immediately, and if you watch closely, you can see little chunks fly out, which are piece of a ice that were instantly frozen by the liquid nitrogen. That’s really, really cold!

Making a ‘smoke cloud’ with liquid nitrogen

Follow this blog or subscribe to the Yuck Science youtube channel to see more liquid nitrogen demonstrations soon!

Public Science – Elephant Toothpaste!

Elephant toothpaste foam swirling in front of Empires13 mural

I hit the streets again and did some elephant toothpaste demonstrations with passersby in front of a really cool mural near downtown Houston. Check out the video below!

Elephant toothpaste is getting to be a really popular science demo! It is a chemical reaction using hydrogen peroxide and a catalyst to increase the release of oxygen. The oxygen in caught in dish soap, creating the foam. I use potassium iodide as the catalyst and a really strong hydrogen peroxide for a really big effect, but those chemicals require careful handling. You can try the demonstration safely at home using the instructions below!

Continue reading “Public Science – Elephant Toothpaste!”

Student Art

Occasionally, students share drawings inspired by the show.  Here is one of a girl getting covered in slime!  If you would like to submit a photo of your drawing to be published here, you can ask a parent to help you send one.  Be sure to do your very best . . . a lot of people might see it!

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How to Make Slime

The number one question kids ask at the end of each show is what’s in the slime!  There are many, many different recipes for making slime.  The one I use, I call “theatrical slime” because it is somewhat different from the types used in science experiments.  It is completely non-toxic and non-staining, and it is even safe to eat (though I wouldn’t recommend it).  Perfect for sliming your friends!

Ingredients:

6 quarts of water

1 box of corn starch

green food coloring

Instructions:

Pour water into a large pot.  Stir in corn starch, breaking up any clumps.  Add 5-6 drops of food coloring, or more if you like.  Bring to a boil (with parent supervision).  Reduce to medium-low heat and let simmer for 20-30 minutes, or until slime begins to thicken.  Rinse the pot before the slime dries so it will be easier to clean.  LET IT COOL THOROUGHLY before use.  When I need slime in a hurry, I add ice at the end.  Makes one big bucketful, or enough to slime yourself and a friend.

Souvenir Merchandise

Yuck Game Show t-shirts and other merchandise are available through Cafe Press.  These items were made available for the kind folks who ask for souvenir items.  The prices are set by Cafe Press, and I have opted to receive any of the money from purchases to keep prices at least somewhat low.