How Do Glowsticks Glow?

istock.com/setsukon
istock.com/setsukon

Picture an atom. Now picture that atom getting excited. Maybe its birthday is coming up. Anyway, when an atom or a molecule gets excited, its electrons' energy levels go up. When the electrons fall back down to their normal state, they release energy in the form of photons, a basic unit of light.

For most of the lights we make and use, those excited atoms release heat as well as light when they’re coming back down. Sometimes you want the latter without the former, a “cold light” like the kind made by fireflies. In the early 1960s, U.S. military and industry scientists knew that the key to making cold light on their own was chemiluminescence, the emission of light from chemical reactions. They just weren’t sure which materials and reactions they were after (luminol had been around for a little while, but had limited applications).

Edwin Chandross, a chemist at Bell Labs in Murray Hill, N.J., was one of the researchers working on the problem.

He wondered if peroxides – chemical compounds with an oxygen-oxygen single bond that could potentially liberate a lot of energy in some reactions - might do the trick. He tried a few experiments and found that hydrogen peroxide combined with oxalyl chloride and a fluorescent dye produced the cold chemical light he was after. The reaction’s efficiency was only about 0.1% (far short of fireflies’ near 90%), but it was a start.

Chandross began corresponding with Michael Rauhut at American Cyanamid in Stamford, Connecticut, and Rauhut’s team expanded on Chandross’ research, searching for ways to make the light bright enough for practical use. They eventually came up a diphenyl oxalate ester that reacted with hydrogen peroxide to make a bright light, trademarked their creation as Cyalume, and rolled it out on the market.

The reaction that happens inside a glowstick goes a little something like this:

- The typical glowstick contains an oxalate ester and dye solution within a plastic stick, and hydrogen peroxide within a small, fragile vial in the middle of the stick.

- When you bend the stick, the vial breaks open, and all the chemicals come together. The oxalate ester and hydrogen peroxide react, sometimes with the help of a catalyst, to form a peroxyacid ester and phenol.

- The peroxyacid ester decomposes to form more phenol and carbon dioxide, producing energy that excites all the molecules floating around in this little party, which then release photons, making the stick glow.

Since the glowstick’s invention, researchers have been fiddling around with this reaction, searching for fluorescing dyes to make different colors (green and yellow are said to be easy to make, while a good purple is near impossible) and adjusting the concentrations of the chemicals to brighten the glow or prolong its life.

American Cyanamid eventually sold its chemical light division, Omniglow. The R&D department there has continued to expand the uses and capabilities of glowsticks, creating luminescent intubating scopes and researching more efficient reactions and glow sticks that work at below-freezing temperatures.

This Gorgeous Vintage Edition of Clue Sets the Perfect Mood for a Murder Mystery

WS Game Company
WS Game Company

Everyone should have a few good board games lying around the house for official game nights with family and friends and to kill some time on the occasional rainy day. But if your collection leaves a lot to be desired, you can class-up your selection with this great deal on the Vintage Bookshelf Edition of Clue for $40.

A brief history of Clue

'Clue' Vintage Bookshelf Edition.
WS Game Company.

Originally titled Murder!, Clue was created by a musician named Anthony Pratt in Birmingham, England, in 1943, and he filed a patent for it in 1944. He sold the game to Waddington's in the UK a few years later, and they changed the name to Cluedo in 1949 (that name was a mix between the words clue and Ludo, which was a 19th-century game.) That same year, the game was licensed to Parker Brothers in the United States, where it was published as Clue. Since then, there have been numerous special editions and spinoffs of the original game, not to mention books and a television series based on it. Most notably, though, was the cult classic 1985 film Clue, which featured Eileen Brennan, Tim Curry, Madeline Kahn, Christopher Lloyd, Michael McKean, Martin Mull, and Lesley Ann Warren.

As you probably know, every game of Clue begins with the revelation of a murder. The object of the game is to be the first person to deduce who did it, with what weapon, and where. To achieve that end, each player assumes the role of one of the suspects and moves strategically around the board collecting clues.

With its emphasis on logic and critical thinking—in addition to some old-fashioned luck—Clue is a masterpiece that has stood the test of time and evolved with each decade, with special versions of the game hitting shelves recently based on The Office, Rick and Morty, and Star Wars.

Clue Vintage Bookshelf Edition

'Clue' Vintage Library Edition.
WS Game Company

The Vintage Bookshelf Edition of Clue is the work of the WS Game Company, a licensee of Hasbro, and all the design elements are inspired by the aesthetic of the 1949 original. The game features a vintage-looking game board, cards, wood movers, die-cast weapons, six pencils, an ivory-colored die, an envelope, and a pad of “detective notes.” And, of course, everything folds up and stores inside a beautiful cloth-bound book box that you can store right on the shelf in your living room.

Clue Vintage Bookshelf Edition is a limited-release item, and right now you can get it for $40.

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Systemic vs. Systematic: How to Use Each Word Correctly

This woman systematically drinks orange juice while her creative juices are flowing.
This woman systematically drinks orange juice while her creative juices are flowing.
m-imagephotography/iStock via Getty Images

The English language is bursting with pairs of words so similar you might think they mean the same thing, even if one has an extra syllable in the middle. Some actually do mean the same thing—disorientated, for example, is a version of disoriented more commonly used in the UK, but they both describe someone who’s lost their bearings.

Others, like systemic and systematic, have different definitions. According to Dr. Paul Brians, a former Washington State University English professor and leading authority on grammar, systematic relates to an action that is done “according to some system or organized method.” If you sort your M&Ms by color and eat the blue ones last, you’re doing it systematically. Sometimes, Brians explains on his website, systematic is used when a behavior—however unintentional it may be—is so habitual that it seems to be the result of a system. If you forget to lock your front door every time you leave the house, someone might say that you have a systematic pattern of forgetfulness.

Systemic, meanwhile, describes something that happens inside a system or affects all parts of a system. It’s often used in scientific contexts, especially those that involve diseases or pesticides. If a cancer is systemic, that means it’s present throughout the body. If you’re describing how the cancer progressed, however, you could say it spread systematically from organ to organ. As Grammarist points out, systemic can also denote something that is “deeply ingrained in the system,” which helps explain why you sometimes hear it in discussions about social or political issues. When Theodore Roosevelt served as the New York City Police Commissioner, for example, his main goal was to stamp out the systemic corruption in the police department.

In short, systematic is used to describe the way a process is done, while systemic is used to describe something inside a system.

[h/t Grammarist]