Trick Candles

One of the common things when you go to birthday parties is candles. Candles in cupcakes, brownies, cookies, ice-cream cake, just about any dessert you can think of. But no matter what medium the candle is in, on must beware of the dreaded TRICK CANDLE!

That’s right! The candles that never go out. But how do they work? And why on earth would someone create them?

Usually, when you blow out a candle, you see or smell smoke, and if you watch closely, there are still embers left over that glow red-hot. My friend Lindsey’s post summarizes it well. She writes, “To explain trick candles, let me explain regular candles first. After you blow out a regular candle, little smoke comes off the wick, and this is vaporized paraffin. Paraffin in vaporized paraffin is candle wax.” Now, if you haven’t already read my post on candles, click here to learn more! The embers left after the candle is blown out is hot enough to vaporize paraffin, but not to light it up again. However, in a trick candle, that’s exactly what you need to do. The key is to add something to the candle to make it continuously light up, even when blown out.

The most common “key” used is magnesium, as it is a metal, making a good conductor that can burn. One article states, “Inside the burning wick, the magnesium is shielded from oxygen and cooled by liquid paraffin, but once the flame goes out magnesium dust is ignited by the ember. If you watch the ember you will see tiny flecks of magnesium going off. One of them produces the heat necessary to re-light the paraffin vapor, and the candle flame comes back to life!” In other words, the magnesium is protected and cooled, but is vulnerable after the candle goes out, allowing it to be the “lighter” of the new flame, and so on and so forth.

Trick candles are cool, but some people may not like them. Then again, you can use it as a prank for your annoying older sister…

Links:

http://science.howstuffworks.com/innovation/science-questions/question420.htm

http://chemistry2013-14.tumblr.com/post/67269673550/relating-it-back-to-chemistry-trick-candles

So ta ta for now and I hope to see your chemical reaction soon!

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Not Nice Spice vs. Timely Tranquilizer

Hot, hot, hot! That’s why most people don’t like spice! Not that I love spicy foods, but I can take my fair share. But when enough is enough, there never seems to be anything to put out the fire in my mouth. Water doesn’t help, but one drink readily available for most can stop the fiercest of fiery mouths. That drink is milk.

In certain foods like peppers, there is capsaicin. This also appears in spices like oregano, cinnamon, and cilantro. It is completely odorless, and, according to one article, “A solution that contains only 10 parts per million produces a persistent burning sensation when placed on the tongue.” You can taste it better when there is less of it. The burning flavor comes form a long hydrocarbon tail. It can bind strongly with lipotein receptors. Its fatty tail allows it to move easily through lipid-rich membranes, making the taste fiercer.  Based off what the website said, the compounds have different structures that are very similar. This is the reasoning behind where the burning sensation is. For some peppers, it may be in the mouth, while others in the throat.   The reason for associating the burning sensation for being hot? “The capsaicin key opens a door in the cell membrane that allows calcium ions to flood into the cell. That ultimately triggers a pain signal that is transmitted to the next cell.”  The same thing happens when cells are exposed to heat. That means that  chili and heat burns are similar at the molecular, cellular, and sensory levels.

That still doesn’t explain why water doesn’t help. Capsaicin is insoluble in cold water, but freely soluble in alcohol and vegetable oils. Small amounts alcohol won’t help though, so milk is a better remedy.  “Milk contains casein, a lipophilic (fat-loving) substance that surrounds and washes away the fatty capsaicin molecules in much the same way that soap washes away grease.” But even after you know you can eat spicy foods and still be able to cool yourself down, don’t eat too much! Too much of a good thing is not good at all, and capsaicin is the same!  Capsaicin prevents nerve cells from communicating because it blocks the production of certain neurotransmitters and can even destroy cells! In the past, capsaicin has even been used as a weapon. “The Mayans burned chiles to create a stinging smoke screen, and threw gourds filled with pepper extract in battle.” Today, it is commonly used in pepper spray. It can also be used to relieve pain, after exposure and tolerance to it builds. Some people, if they regularly eat spicy foods, can enjoy it, as endorphins are released after you are comfortable with the taste, making it a pleasant experience.

While I don’t eat spicy foods often, I do love salsa and other spicy things, as long as it isn’t too much in one serving! While I may not get a rush from eating spicy foods, I do enjoy the mouth on fire feeling for a few seconds (and then I just get thirsty!). At least now I know I should drink milk, instead of drinking water!

Links:

http://antoine.frostburg.edu/chem/senese/101/features/capsaicin.shtml

So ta ta for now and I hope to see your chemical reaction soon!

The Terminator Returns?

I was on Yahoo! the other day and I was going through those thumbnails at the top, you know, the ones with the important news? I came across this one post that I clicked on, and it talked about a polymer that can, get this, HEAL ITSELF! So I just had to find out more!

Created in Spain, this polymer can be sliced in half, left on a table for two hours at room temperature, and reheal itself up to 97%! There is still scarring, but, no matter how hard you try, it will not rip at that spot.

According to one article,  “Self-healing polymers mend themselves by reforming broken cross-linking bonds. However, the cross-linking healing mechanism usually requires an external stimulus.” Most of the time, the triggers are energy inputs like heat or pH. “Self-healing polymers that can spontaneously achieve quantitative healing in the absence of a catalyst have never been reported before, until now.” Other attempts have been made before, like Ibon Odriozola of Spain. However,  it was not appealing enough to market to the public. During the video above, the Terminator is cut in half and then left in two pieces atop each other for 2 hours in room temperature. The material? An industrially familiar, permanently cross-linked poly(urea–urethane) elastomeric network.

Many chemists believe this elastomer can be used to “… improve the security and duration of many plastic parts, for example in cars, houses, electrical components and biomaterials.”

I believe this is just the start to developing long lasting items. With this technology, we can develop more realistic things found in nature. Developing new products such as for use in the human body would be amazing. If we were to refine this, fake skin could be modeled out of it! And from there! Oh, the places we’ll go!

Links:

http://news.yahoo.com/blogs/this-could-be-big-abc-news/terminator-plastic-polymer-heal-itself-014827978.html?vp=1

http://phys.org/news/2013-09-self-healing-polymer-spontaneously-independently.html

http://www.rsc.org/chemistryworld/2013/09/polymer-regenerates-elastomer-heals-independently

So ta ta for now and I hope to see your chemical reaction soon!