No picnic would be perfect without ketchup. But ketchup has this habit of taking its sweet time when leaving the bottle.

There are several ways to get ketchup out of the bottle.

  • Stick a knife in it and scoop it out.
  • Hit the bottle at the neck (where the 57 is located).
  • Skip it and use mustard instead.

But there is a better, scientific way:

Shake the bottle.

Ketchup is made up of tomato pieces, water, vinegar and spices. And, it is the arrangement of the tomato pieces that give ketchup a structure and cause the flow of ketchup to slow down.

Scientists would call ketchup a thixotropic yield stress liquid. The yield stress part means that it takes force for the ketchup to move. This is why we have to hit the bottle to get it out. The thixotropic means that the ketchup has the ability to “remember.”

Once someone has used the ketchup bottle, the ketchup inside “remembers” it and will flow faster afterwards. This means that the second person that gets the ketchup bottle will have an easier time getting the ketchup out then the first person to use it.

What is going is on is that the tomato particles in the ketchup get rearranged after the first use and can easily flow passed each other the second time.

So how do you get ketchup to flow faster? If you are the first person with the ketchup bottle, then shake it. But, if you are the second person, don’t worry; you won’t have long to wait. The ketchup will flow real easily.

So, next time you are at a picnic, let someone deal with the ketchup bottle first. It is polite and scientifically a better way to reduce the wait.

 

Fabrics are an old invention and have been important to us since ancient times. We choose different fabrics for their comfort or protection or both. For example, cotton absorbs moisture. And, this is a good thing, because the body doesn’t like wetness right next to the skin. The wetness feels clammy and it is very uncomfortable.

But in this age of technology, textiles will do more than make us comfortable. They will give us information, because they will have small bits of electronics embedded in them.

In fact, companies are now making wearable technologies to help NFL coaches monitor athletes by tracking their heart rate and their oxygen intake.

So when might you see smart shirt at your local store?

Well, engineers are working on them now. Ends up that a shirt is the worst place for electronics. Wearing a shirt or washing a shirt are demanding environments for any kind of electronics. They are the opposite of what electrical components prefer. Electronics like to keep dry and not bend.

These are major challenges engineers are solving right now. It seems in the future, we might need to charge our shirts. Or at least carry extra batteries.

Ben Franklin went out one stormy night with a kite and found out that lightning is electricity. Well, lightning has a few other tricks up its sleeve. Lighting makes magnets that are called lodestones.

Lodestones have been part of civilization for thousands of years, since the early compasses, which allowed us to reach new corners of the earth. And, the unusual origin of lodestones has been known for decades. The first clue that these stones were otherworldly was that they are only found on the surface of the earth. If you dig deep into a mine, you won’t find lodestones.

Dr. Peter Wasilewski, a retired NASA scientist, who made a living playing with lightning had this to say, “The thing about the lightning bolt, besides being magical, is that it has a magnetic field associated with it.”

Lightning changes the stone by providing a big magnetic field. One can demonstrate this by rubbing a needle with a magnet. That needle will be a magnet for a short time. Well, the lightning and lodestones undergo a similar process but on a larger and supernatural scale.

So, how do you coax lightning to strike a stone?

Wasilewski created lodestones using lightning in much the same way as Ben Franklin did, but with tools that are much more expensive. To make a lodestone, first he had to go where there is lots of lightning. Summertime months in places like Florida and New Mexico are hotspots for strikes.  Then, he needed a better “kite.” Wasilewski replaced Franklin’s contraption with a small bottle rocket that he launched into storm clouds. Attached to this rocket was a three-mile long metal wire fastened to a plastic box. Inside the box was a bed of sand, and the soon-to-be-zapped rock sat on top.

The experiment happens in a flash and everything melts or burns, since the lightning heats everything to over 2,900°F.

And the rock in the box? It’s a magnet now.

That’s a very striking difference!

 

There have lots of news about various pandemics. The first line of defense is a camera, a thermal camera.

When someone is sick, they usually have a temperature. Here is where the camera comes it. Thermal cameras can “see” if someone has a fever because these cameras can detect the heat. Thermal camera detect the heat, which comes off as infrared.

 

And this year’s Oscar goes to .   .    .   chemistry.

On that wonderful night in LA, the red carpet is full of celebrities and fans all eager to hear who wins the gold statue.  However, the Oscar statue isn’t pure gold. That would be extremely expensive.  The Oscar is actually a bronze statue that is coated with gold.

So how does the Oscar become, well, an Oscar?

To understand we have to think about frog’s legs.

In the late 1700s, Luigi Galvani, who was a professor of anatomy in Italy, was dissecting frogs using a metal scalpel and a copper clamp. He noticed something: The frog’s legs twitched like they were alive! He repeated this a couple of times and they twitched every time.

He found something amazing and called it animal electricity. That is the animal had some supernatural life force inside of it. Galvani wrote up his results and all of Europe embraced this idea.

But, on the other side of Italy was a physics professor named Alessandro Volta. He believed in Galvani’s idea at first, but began to think it was the two different metals that caused the legs to twitch. Volta recalled an earlier experiment by another scientist who had put his tongue between two different coins, and it created a terrible taste. Ends up, that  the two metals next each other in a liquid (saliva, in this case) started a chemical reaction.

So with this old experiment in the back of his mind, Volta made sandwiches of two different metals and put them in a jar full of saltwater. Then, he connected wires from this stack of metals to the frog’s legs. They twitched.

What Volta showed is that two different metals together make electricity. He made a battery.

In a battery, electricity flows from one metal to the other.

But what does this have to do with the Oscars?

Well, in order for electricity to flow in a battery in one direction, there has to be metal flowing in the opposite direction.  If you were to look at the metal under the microscope you would see that a metal coating is starting to form.

So to make an Oscar this coating process is taken to a much bigger level.  The bronze statue is put in a huge chemical tank that has microscopic gold floating in a liquid. Electricity is attached to the statue and the gold particles become attracted to the statue and start to coat it. After a really long time in the tank, the statute becomes the beautiful icon we know today.

So, if you enjoy the Oscars, and many do, you really have frog’s legs to thank.

References:

Luigi Galvani: Bern Dibner

How the Oscar Got a Facelift this Year

How Frog Legs Helped Make the Oscars Possible (Video)

When the voice in the commercial says “chocolate melts in your mouth and not in your hands,” well they aren’t joking. Scientifically, it is true. Chocolate melts around 92 degrees Fahrenheit, while your mouth is 98.6 degrees. (Your hands are only 60 degrees.)

Chocolate comes from a seed housed in football-shaped pods, which sprout from a tree called Theobroma cacao. This name literally means food from the gods. This tree grows along the Equator in places like Ghana, Nigeria, the Ivory Coast, Indonesia, Brazil, and Ecuador.

Chocolate is an old food. Montezuma, the ancient Aztec emperor, drank 50 jars of a chocolaty drink to increase his vitality and virility. But, what he drank was very different from the hot cocoa we drink today.

It takes many many steps to make modern chocolate. First, when chocolate farmers open the fruit, the seeds do not look appetizing, that is because the cocoa beans are surrounded by a white gooey mash. “It looks pretty disgusting,” said Gail Ambrosius, a chocolatier based in Madison, Wisconsin. But if you were to taste these beans, you’ll be surprised. “It tastes just amazing. Kind of like honeydew, melon, apricot, peaches. It is just delicious, ” she said.

Once the cocoa beans are taken out, then the transformation begins. The beans are tossed in a large box to ferment, which generates lots of heat—especially after about a week. After that the cocoa beans are laid out on a black tarp to dry. And sorted to remove any stones that might be there. Then, the beans are roasted. “It teases out the final flavor of the beans,” said Ambrosius. The cocoa beans are then crushed and at this point they are called cocoa nibs. And with heat and pressure, you get a drippy melted chocolate, which is called cocoa liquor.

After all of that, a decision has to be made: Are you making a dark chocolate, a milk chocolate, or cocoa powder?

So then you do the math.

“If you’re making a 70 percent chocolate and you’re making a thousand pounds total, you would put 700 pounds of the liquor in your machine and 300 pounds of sugar. So there you get the 70 percent chocolate,” said Ambrosius.

Interestingly, the higher the percentage of cocoa, the healthier the chocolate is. Some studies suggest dark chocolate raises the good cholesterol—and lowers the bad.

But remember, chocolate has lots of sugar—as much as soda. So eat a little bit and savor all the tasty chemistry in your mouth.

LEDs or light emitting diodes are everywhere from traffic lights to Christmas ornaments to remote controls.  Inside these tiny bulbs is a small grey block which is made of silicon. And, silicon has the unusual origin of coming from sand.

Sand is melted and purified and then cast in long thick logs, called ingots, which are slice like baloney. Twenty years ago, these logs used to be as thick as a thumb, now these logs are wider than dinner plates.  The slice is then cut into small square chips.

The chips are then given a bit of phosphorus on one side and a bit of boron on the other. Phosphorous is an element that has more electrons than silicon; boron has fewer electrons than silicon. These different sides are connected to a battery. The battery pushes electrons from the phosphorous side to the boron side. And, when these electrons connect with atoms that don’t have electrons, light is given off.

LEDs are more efficient than incandescent bulbs. Incandescent bulbs, the ones we attribute to Thomas Edison, give off lots of heat. This is why toy oven use these bulbs to bake small cakes.  In fact, 70 percent of the energy used by incandescent bulbs is heat. That’s wasted energy.

But, LEDs run cool. They are so cool that cities now must remove snow from LED traffic lights during the winter. In the past, incandescent bulbs ran so hot, they would burn off any snow that landed on them. LEDs are not running hot and so snow collects on traffic lights. (This happens when you solve one problem, you inherit another one.)

So, as you can see, small bits of beach sand purified into silicon are made into sandwiches that give off light. Now, this is a bright idea.

 

Additional reading & activites (Affiliate Links):

Elements: A Visual Exploration 

Snap Electronics Fun LED kit

Materials: A Very Short Introduction