Phillip Cook

Rubber tires are essentially composed of a single molecule of cross linked polyisoprene. The old tire patches I use in this video are little more than metal discs filled with a combustable mixture with a thin rubber patch on the underside. When the mixture is ignited, it gets hot enough to cause the rubber in the patch to vulcanize with the rubber in the tube, creating a strong airtight patch, in spite of the fact that these patches are more than 75 years old! #c#chemistrychemteacherphil #LearnOnTikTok

It is surprisingly easy to make your own fuel gel. All you really need are three ingredients: eggshells, vinegar and alcohol. Gel fuels like sterno, are useful because they provide a clean burning flame with minimal risk of spilling the fuel. Making a gel fuel requires encapsulating a combustible liquid inside a gelatinous solid. In this case, I make the gel by first creating a solution of calcium acetate, the primary biproduct of the reaction between the calcium carbonate in eggshells and the acetic acid in vinegar. Boiling the liquid concentrates the calcium acetate, which is really soluble in water, but much less soluble in alcohols. So when the alcohol fuel is added, it immediately causes the calcium acetate to precipitate out as a solid, trapping the alcohol in the process, and forming a colorless gel that works really well for toasting marshmallows! #c#chemistrychemteacherphil #LearnOnTikTok

Cranberry juice is a natural pH indicator. #chemistry #chemteacherphil #LearnOnTikTok

This is a very real toy designed for twelve year olds in 1936 by the A.C. Gilbert Company. And yes, it used molten lead to cast toy figures. Lead is a very toxic metallic element that can cause all kinds of developmental and neurological problems. However, handling toys made of lead is actually very low risk, especially if you wash your hands after handling the lead figures. This is because solid lead is not easily absorbed through the skin. This does not mean that we shouldn’t be worried about exposure to lead. Inhaling lead dust, or accidentally ingesting lead paint can lead to severe health issues. But with this toy, the main risk aside from the molten lead is the burn hazard it presents. The melting point of lead is 327.5 degrees Celcius (621 degrees F!) and there are lots of really hot surfaces on the toy as it is operated. I’ll bet lots of kids in the 1930s that had this accidentally burned themselves more than once!  #chemistry #metallurgy #chemteacherphil

If you could see on the atomic scale and looked at a latex balloon, you’d see holes! Holes large enough for atoms of helium to fit through. This is one reason why latex balloons deflate so rapidly when inflated with helium gas. Helium atoms are very small, much larger than the nitrogen and oxygen molecules that make up the majority of the air we breathe. So what makes other types of balloons, like mylar, so much more effective in trapping helium? Mylar balloons are comprised of three layers of different materials: nylon, aluminum and polyester. This combination makes it much more difficult for tiny helium atoms to find a way through, and mylar balloons can consequently remain inflated and floating for weeks! #chemistry #chemteacherphil

Its annoying when videos get muted. #chemistry #chemteacherphil #LearnOnTikTok