Make: Online: Chemistry Archives

Archive: Chemistry

November 3, 2009

Functioning X-men "Pyro" costume flamethrower appliance

OK, my awesome meter has kind of overloaded on this one. Everett Bradford's "Prometheus Device" is a hand-mounted appliance that shoots, like, real fire. It looks, you know, dangerous, and all, but it's so cool I don't really care. And he's done a great job documenting the build, although obviously no one should attempt this who doesn't know what they're doing. Amazing work, Everett. Thanks!

Make: Halloween Contest 2009

There's still time left to enter the Make: Halloween Contest 2009! Deadline is 11:59 PM PST, November 3rd. Show us your embedded microcontroller Halloween projects and you could be chosen as a winner.

October 31, 2009

Pumpkin abuse in the name of science

Over at the Periodic Table of Videos, their chemists put pumpkins through the ringer to demonstrate properties of various chemicals, states, and processes. Nice to see Halloween getting the whole "Peeps in the microwave" treatment. [Thanks, Shawn!]

Periodic Table of Videos

More:
See our own growing collection of chemistry experiments in the Make: Science Room

October 30, 2009

Periodic taxi

Follow up - Bruce sent this in "Periodic taxi"!

Periodic table

Ptable
A maker sent this in, nice table!

October 29, 2009

Flammable ice

This awesome little chemical machine is from Mr. Kent's chemistry page. Ice is laid in a Pyrex dish over a layer of calcium carbide. As the ice melts, the liquid water reacts with the carbide to produce acetylene gas, which of course is highly flammable. A match starts it off, and then it burns continuously on its own. My first thought was that the system could rapidly spiral out of control--more heat melts more water makes more gas makes even more heat. But it's limited by the amount of oxygen that can get down into the pan, I think. My second thought was that maybe a bit of sodium metal down there with the carbide could make the process self-igniting.... (For God's sake, no one try that.)

Lots of great new Science Room content

We've got lots of new content in the Make: Science Room, including a whole new Forensics series on the many methods of fingerprinting. Tired of those bitter family disputes over who ate the last ice cream sandwich? Take the wrapper to the lab and find out for sure!

We also have a lab on testing for lead paint and an introduction and series of labs on colloids and suspensions. What in blue-blazes is a colloid, you ask? Why it's a "two-phase heterogeneous mixture made up of a dispersed phase of tiny particles that are distributed evenly within a continuous phase." Think: homogenized milk. It has tiny particles of liquid butterfat (the dispersed part) suspended in water (the continuous part). That's a colloid.

And then there are sols, that's a "solid phase dispersed in a liquid continuous phase. Ordinarily, a sol is a liquid, but it can be converted to a semi-solid gel by adding a gelling agent. In some cases, the solid phase itself may also serve as the gelling agent."

An example of a gelled sol is the notorious Super Napalm B. And guess what? We show you how to make it -- just in time for Halloween. We're kidding. KIDDING! This is serious stuff, a cool experiment, but one with real dangers. This is seriously volatile burning material that's also a seriously sticky gel, a deadly combination (hence the notoriety).

Here's the door to the Science Room >>

In the Maker Shed

And don't forget all of the awesome science-related products now carried in the Maker Shed, including a Latent Finger Printing Kit and a Lead Paint Test Kit (seen above).

October 28, 2009

Interesting cancer resistance in naked mole rats

There's a ridiculous amount of hype in science today, and in an area as sexy as cancer research it is perhaps even worse. In writing this post, I am mindful of the "sharks don't get cancer" trope that's been used irresponsibly to sell shark cartilage as snake oil, very often to people who are in a desperate situation. Consider that a disclaimer.

There is, reportedly, a very low incidence of cancerous tumors in naked mole rats. Statements like "there has never been a tumor found in a naked mole rat" may be misleading unless they also explain to us just who is looking for tumors in naked mole rats, how long they've been doing so, how hard they're looking, who's paying for it, and why. Still, I think this paragraph is interesting:

The findings, presented in today's issue of the Proceedings of the National Academy of Sciences, show that the mole rat's cells express a gene called p16 that makes the cells "claustrophobic," stopping the cells' proliferation when too many of them crowd together, cutting off runaway growth before it can start. The effect of p16 is so pronounced that when researchers mutated the cells to induce a tumor, the cells' growth barely changed, whereas regular mouse cells became fully cancerous.

Of course, there's all kinds of reasons why it might work for naked mole rats and not for people, but the idea that a mechanism as simple as cellular "claustrophobia" might go so far to eliminating tumors is pretty interesting. Here's the original abstract at PNAS.

October 27, 2009

Super cements aka "geopolymers"

Think cement is just cement? Not so. These unlovely mugs are nonetheless very special. Prepared from special synthetic aluminosilicate materials called "geopolymers" (Wikipedia) by members of Dr. Waltraud M. Kriven's research group at The University of Illinois Urbana-Champaign, these mugs were tested in a special "mug drop" event at the 2004 American Ceramic Society (ACeRS) conference, and supposedly "were impossible to break at even 50ft onto bare concrete" (although the photos clearly show an astroturf-covered floor). Danger Room's David Hambling recently posted a nice overview of geopolymer technology with an eye towards defense applications. These presentation slides by Dr. Kriven (.pdf) include some actual formulae.

October 26, 2009

Bob Thompson on laboratory scales

Bob Thompson, our resident Make: Science Room lab geek, answered a question in the comments for the "Setting Up a Home Science Laboratory Part II - Gearing Up" topic, about buying digital scales. I thought it was worth posting here for the benefit of others.

Cynthia asked:
What would you recommend in the way of a digital scale for intermediate/high school science? I was thinking of purchasing one that was a 1000 g capacity with a 0.1 sensitivity. Could this both serve chemistry and physics, etc.?

Bob's reply:
Good question. The two big trade-offs in buying a balance are capacity and resolution. Ideally, we'd all like an inexpensive balance with 0.0001 gram resolution, but unfortunately, there aren't any such animals.

The balance I chose two or three years ago for my own home lab is the desktop MyWeigh iBalance 201, which has 200 gram capacity and 0.01 gram (centigram) resolution. That's still a current model, and is available in Maker Shed and elsewhere. However, it's also a $100+ balance.

If you're looking for something a bit less pricey, Maker Shed also carries a portable $33 electronic balance (on sale through 10/31 for $29) that has the same 200 gram capacity and 0.01 gram resolution. I have one of those as well, and it's a very nice little scale. I suspect it probably isn't quite as durable as the i201, but OTOH, it's less than a third the price. (It's also useful around the house. My wife just used it yesterday to see if she needed to put a second stamp on an envelope.)

My take on this is that 200 g is sufficient capacity. Almost any experiment you do that would use the 1000 g capacity of the balance you're considering can be scaled down to work within the 200 g capacity of these balances. OTOH, having 0.01 g resolution instead of 0.1 g resolution is very nice, particularly for chemistry.

It'll also save you money on chemicals. For example, if you need to make up a solution to a particular accuracy, being able to weigh out (say) 7.87 g of the chemical and making up 100 mL of solution is cheaper than having to weigh out 78.7 g of the chemical and make up 1,000 mL of the solution.

This way to the Make: Science Room >>

October 23, 2009

How-To: Make chemiluminescent soap bubbles

No photos yet. That's a homework assignment for the bubble chemists in the audience. But I couldn't resist sharing my excitement over this paragraph from US patent 5,246,631 for glowing soap bubbles:

An example of practice of the present invention involves using a liquid dish such as LEMON JOY available from Procter & Gamble Company (Cincinnati, Ohio). Although the LEMON JOY may be diluted with varying amounts of water, it is preferred that the dishwashing liquid be used at full strength. Approximately 9 milliliters of CYALUME solution made in accordance with the manufacturers instructions are added to approximately 120 milliliters of the dishwashing liquid. Although this particular mixture may be used to produce adequate self-illuminated bubbles, it is preferred that 3 to 4 drops of glycerin be added to the solution as a bubble hardener. The solution is then ready for use to form self-illuminated bubbles.

I've never actually measured how much Cyalume (Wikipedia) is in a standard glow-stick, but I'm betting you could come up with 9 mL of the stuff by cutting open two or three at most.

October 21, 2009

"The joy of sex don't last like the fun of shootin' anvils"

To "shoot," an anvil, for the record, is to blast it several hundred feet into the air using a charge of black powder. This delightful man, Gay Wilkinson, is apparently the world's champion anvil-shooter. The fireworks start at 1:30. [via Boing Boing]

October 19, 2009

Bubble fogger with black light bubble liquid

More awesomeness from Terra of Halloween Forum. The UV-reactive bubble juice is from Tekno Bubbles.

More:

Make: Halloween Contest 2009

Microchip Technology Inc. and MAKE have teamed up to present to you the Make: Halloween Contest 2009! Show us your embedded microcontroller Halloween projects and you could be chosen as a winner.

October 16, 2009

Litmus candy

Windell of Evil Mad Scientist Laboratories noticed that the "Blueberry Blast" candies he picked up contained red cabbage extract, which, as every evil mad scientist knows, is a classic homebrew pH indicator. So he dunked three samples in baking soda solution, neutral water, and vinegar. Sure enough, visible color changes.

October 15, 2009

Suspended animation with hydrogen sulfide?

It may smell like rotten eggs, but it turns out H₂S may be able to slow down the chain of chemical degradation that causes death in cells that are deprived of oxygen. Biologist Mark Roth can supposedly take a lab rat, stop its heart with a dose of hydrogen sulfide, and bring it back to life an hour later just by turning off the gas. Quoting now from this article at CNN.com:

Scientists are starting to understand that death isn't caused by oxygen deprivation itself, but by a chain of damaging chemical reactions that are triggered by sharply dropping oxygen levels. The thing is, those reactions require the presence of some oxygen. Hydrogen sulfide takes the place of oxygen, preventing those reactions from taking place. No chain reaction, no cell death.

Roth has won a MacArthur grant for this work, so there's a better-than-average chance that it's more than just hype.

October 14, 2009

Very small hollow metal spheres

Tiny metal spheres are needed for tiny ball valves and tiny ball bearings, which are needed for all kinds of miniaturized machines. Hollow spheres are lighter, and thus have less inertia, and thus can be made to move faster in these very small applications, where response time is often critical. But how do you make a hollow metal sphere 2mm across? Turns out you can do it with one of the lost foam processes I'm always going on about. Tiny styrofoam beads are first coated with fine metal powder and a binder, then heat-treated to evaporate both binder and bead, leaving only a fragile hollow metal powder shell, which is then sintered into a continuous shell at higher temperature. Read more over at Science Daily.

October 9, 2009

Cash awards for amateur scientific apparatus designs

In an effort to advance the cause of citizen science, Michael Wood is offering a total of $400 in prize money to anyone who can produce reliable, low-cost (<$100US) DIY scientific apparatus capable of meeting one of four design objectives:

First, we require a device capable of producing liquid nitrogen at the rate of at least 100mL an hour.
Secondly, we require a vacuum system capable of pumping down a volume of at least 10cm x 10cm x 10cm to, and holding a vacuum at, 0.01 atm (with pressure measurement).
Thirdly, we require the ability to view objects of small scale with up to 1000x magnification.
Finally, we require a functioning oscilloscope, capable of measuring at least two signals at once, and with multimeter capability, accurate in all measurements to within 1%.

Read all the details at Michael's website.

Make: Projects - Pages of a forbidden tome

They could be from The Necronomicon, Unaussprechlichen Kulten, or simply Poe's "quaint and curious volume," but everybody needs at least a few tattered leaves of ancient mind-blasting arcanum lying around to impress guests. Especially around Halloween.

This tutorial presents an easy method for producing weathered "antiqued" paper with burned edges. The trick of soaking white paper in coffee or tea to give it an old, yellowed look is very familiar, but the process for selectively burning the edges of the paper is something I discovered on my own. A simple and safe chemical treatment is used to selectively char the page, only where it has been applied, upon mild heat treatment.

Read full story

October 7, 2009

The Nobel Prize in Chemistry 2009 - "for studies of the structure and function of the ribosome"

Pt 2224
The Nobel Prize in Chemistry 2009 - "for studies of the structure and function of the ribosome"...

The Nobel Prize in Chemistry for 2009 awards studies of one of life's core processes: the ribosome's translation of DNA information into life. Ribosomes produce proteins, which in turn control the chemistry in all living organisms. As ribosomes are crucial to life, they are also a major target for new antibiotics.
This year's Nobel Prize in Chemistry awards Venkatraman Ramakrishnan, Thomas A. Steitz and Ada E. Yonath for having showed what the ribosome looks like and how it functions at the atomic level. All three have used a method called X-ray crystallography to map the position for each and every one of the hundreds of thousands of atoms that make up the ribosome.

Inside every cell in all organisms, there are DNA molecules. They contain the blueprints for how a human being, a plant or a bacterium, looks and functions. But the DNA molecule is passive. If there was nothing else, there would be no life.

The blueprints become transformed into living matter through the work of ribosomes. Based upon the information in DNA, ribosomes make proteins: oxygen-transporting haemoglobin, antibodies of the immune system, hormones such as insulin, the collagen of the skin, or enzymes that break down sugar. There are tens of thousands of proteins in the body and they all have different forms and functions. They build and control life at the chemical level.

An understanding of the ribosome's innermost workings is important for a scientific understanding of life. This knowledge can be put to a practical and immediate use; many of today's antibiotics cure various diseases by blocking the function of bacterial ribosomes. Without functional ribosomes, bacteria cannot survive. This is why ribosomes are such an important target for new antibiotics.
This year's three Laureates have all generated 3D models that show how different antibiotics bind to the ribosome. These models are now used by scientists in order to develop new antibiotics, directly assisting the saving of lives and decreasing humanity's suffering.

October 5, 2009

"Fiction science" theory of Superman's powers

Ben Tippet A Unified Theory of Supermans Powers Figure 3.jpg

Back in 2005, I wrote a fictional scientific paper (.pdf) postulating that zombiism is in fact caused by a prion, rather than a virus, as is commonly hypothesized. I also wrote a short essay about the idea of "fiction science" at the time. Now Ben Tippet, at the behest of Dinosaur Comics' Ryan North, has written a similarly fictional scientific paper (.pdf) presenting "A Unified Theory of Superman's Powers" from a physicist's perspective. I'd be interested in hearing of other examples of people co-opting the serious literary forms of science for fictional purposes. If you know of one, please drop me a comment. [via Neatorama]

October 2, 2009

Novel edge-collecting solar panels

This is a solar panel. Really. If you've observed that it looks a lot like a piece of live-edge fluorescent acrylic, you're more than halfway to understanding how it works. Light entering the panel from the sides is absorbed by dyes and converted, by some fancy top-secret nano-metal whatnot ingredients, into a kind of internal re-radiation that is collected by conventional silicon applied only at the edges. Fair warning: Full science-hype disclosure rules apply here. The responsible party is Israel's GreenSun, and they do not have a product at market yet. But The Economist seems to be buying in, and their ethos is good for a click or two, in my book.