Kitchen Biology

Many of the chemistry projects that we never got to last year lend themselves to investigation under the heading of biology as well. Although I haven't seen the term "Kitchen Biology" used as often as "Kitchen Chemistry," I've got plans to brew (root) beer (with yeast), make yogurt (with bacteria), and grow bioluminescent bacteria on old fish. Good times ahead!

Be sure to visit my Home Biology blog.

Wood Sorrel

We've been cataloging plant and animal species in our backyard for biology studies and discovered that wood sorrel has a sour, lemony taste to the leaves because of oxalic acid. This acid is also present in many other fruits and vegetables; in fact, according to Wikipedia, if you eat a slice of rhubarb pie with a glass of milk, it will cause some of the calcium to precipitate out, creating tiny grains you can feel on your tongue!

Moving on to Home Biology

The summer has gone and I am starting to add content to this year's science blog, Home Biology. Come join me!

Periodic Table of Videos

Still hoping to do a few outdoor experiments before the summer's over but work -- and unending days of rain -- are making it difficult. Maybe this week...

In the meantime, fellow homeschooling author and blogger Kris Bordessa has post on the Periodic Table of Videos from the University of Nottingham in England. The short videos are hosted by Martyn Poliakoff, research professor and pioneer in the field of green chemistry -- with the best Mad Scientist hair I've seen in a long time!

Kris says her 15 year old spent an hour poring through this site. Check it out!

Chemistry Simulations vs Hands-On

Note: I'm hoping to post at least a couple more experiments here -- one that we are still trying to get to operate as advertise -- before turning our attention to biology for the coming school year. (I've just set up homebiology.blogspot.com in anticipation!)

But in the meantime I'd like to pass along an email my friend and fellow homeschooling parent Paul Fernhout sent our local homeschool email list today with some thoughts on chemistry simulations:

In regard to something else I am looking into, I found a website today I wanted to share by Professor William J. Vining at the State University of NY at Oneonta. He has helped develop free chemistry simulations that should run in most web browsers with a Shockwave/Flash plugin installed. At least most of the first five or ten simulations in the list at that URL should be easy enough to play with about some basic ideas of chemistry (the periodic table, etc.). I think the simulations all go with a specific text book, but the general concepts would apply for any person interested in chemistry even without a specific textbook. Essentially, these are all safe scientific toys which may (or may not) in turn inspire further interest in the topic of chemistry. So, think of most of them more as chemistry puzzles (what could they mean?) than chemistry instruction.

From Prof. Vining's main page:

My principal interest lies in developing and testing educational materials and methods for chemistry. The materials are primarily computer-based multimedia software systems that serve the dual purpose of simulating the exploratory nature of chemical investigation and also make use of graphical advantages of computer systems to better explain chemical concepts. The focus of these programs is to enable students of chemistry to explore chemical concepts in a manner that leads them to discover those concepts independently. Because chemical concepts are based on analysis of experimental results, the software systems we design are centered around presenting the student with information they would obtain from an experiment, along with computer-based tools for analyzing those results. This allows the student to observe trends and choose the appropriate experiment to answer a particular question. Once an area of chemistry has been presented by an interactive experimental simulation, the concept can then be explained using multimedia tools such as videos and animations. Our work involves preparation of materials appropriate for use in general, organic, inorganic, physical, and analytical chemistry. Recent projects have included work on a CD-ROM textbook for general chemistry and currently we are working on modules for organic chemistry.

He has some other resources linked from his main page, like some videos of mixing chemicals (though the one I tried did not play well for me). He also has some downloadable things (for Windows?) I did not try.

The Concord Consortium is another site with high quality free learning resources related to chemistry and other things as well, including for example CC Atoms. But some of these resources are harder things to try as they require Java and perhaps locally installing some things. Many (but not all) of these resources are designed for college courses, but could be fun to just play with for someone interested in chemistry who at least knew a bit to get
started with.

A chemistry simulation is definitely IMHO a good use of computers for older homeschoolers, since real (sometimes dangerous) chemistry sets are hard to get these days, making chemistry otherwise difficult to really explore in detail at home. There are some nostalgia and warnings there in the comments about old chemistry sets by the way (some had radioactive materials). There is a link in the comments to that blog post to a supposedly interesting set at Edmunds Scientific. But that set is $200 and obviously is going to take some supervision and pose some risks.

Scientific Explorer's Fizzy Foamy Science Kit of Safe Chemical Reactions is an example of a ($20) "safe" chemistry-related set we got for our child (age four) but it mostly just has stuff you'd find around the house like oil, baking soda, and vinegar (except maybe citric acid in pure form): "
A container of oil in it had leaked all over everything when we got it, but it cleaned up easily. It has some scientific looking stuff in it (not sure if it would be cheaper to buy it separately), but is probably not very interesting for older kids for that long.

The simulations let you try to do all sorts of things, although may be mainly of interest to older kids since they are more abstract (that is, no fizzing). Obviously, like all simulations, they are still not the same as the real thing, being worse in some ways and better than others. They will help kids get the intellectual challenge of chemistry, but they won't help them gain a sense of confidence in a lab setting they would get with the real stuff. But even if you had the real stuff, I'd suggest the simulations could still be interesting (perhaps even more interesting for a motivated learner).

Thanks, Paul!

Photosynthesis

I've been subbing in the public schools the last couple months (quite an experience after 10 years of homeschooling, but that's another story). Last week I had to go over plants with a class of third graders and then give them a test.

In the review materials, their teacher had given them the following formula:

CO2 + sunshine + water = food

This really made me nuts. When my kids were a little younger, I made it a point to find out just how plants turned sunshine into food. It took some doing, but I finally found a DK book that spelled out the relevant chemical formula. Which is this:

6CO₂ + 12H₂O + sunlight ---> 6O ₂ + C₆ H₁₂O ₆ + 6H₂ O
or...
carbon dioxide + water + sunlight --->
oxygen + carbohydrate + water

Now, she's already given them a chemical name (CO2 -- I asked and one child identified it as carbon dioxide). She could very easily have then given them H2O, water, and then done the math. The carbohydrate, glucose, is a form of sugar, which they would have readily understood -- especially here in upstate NY, where maple sugaring is common!

Actually, I was surprised to see "sunlight" in the actual formula; it provides the energy via chlorophyll, a green pigment that absorbs energy from sunlight. But most amazing of all --

THERE WAS NO MENTION OF CHLOROPHYLL!

(And photosynthesis was hand-written in on the test as an afterthought; I had to help the students out by letting them know that photo means light and synthesis is making something.)

Just to understand, as with most public-school science in my experience, the information the kids had to know was basically all vocabulary. For instance, they had to correctly label the cotyledon of a seed. Now, I doubt there are many adults who can identify cotyledon but not chlorophyll. Really.

Anyway, here, for the record, is my third-grader-friendly, chemistry-literate explanation of how plants make food. I am looking forward to exploring biology again (my plan for next year) in light of my ever-growing comfort with chemistry.

Radioactive Elements

I became interested in radioactive elements after my brush with thyroid medicine, and I started looking on eBay for a cheap Geiger counter. (My dad, who worked with X-ray machines, brought one home and demonstrated it for us when I was a kid -- another example of how early impressions about science can stick with you.) Before I could finish my research, a friend bought one for us. Turns out, what we actually have is a radiation detector intended for survivors of nuclear war. As one site I read said, if this thing shows a reading, evacuate!

So when I wanted to look at some common household radioactive items, we still didn't have anything to measure them with.

(This didn't work.)

So we found some nice videos on YouTube from people who did have real Geiger counters.

Among the radioactive items people collect or have about are:

smoke detectors (Americium)
salt substitute (potassium isotope)
Fiestaware dishes (the famous orange-y red made with uranium)
gas lantern mantles (a favorite of The Radioactive Boyscout)
old luminous watches (radium)

But here in Saratoga Springs, NY, we have one source of radioactivity that is less common: mineral water.

Back in the 1800s, Saratoga was known for its horse racing, its casinos, and its spas. Its many springs, the result of a geological fault which runs right through the center of the city (it's a low point known until recently as "The Gut", but now the source of trendy new restaurants). Apparently radioactivity is one requirement for "really good" mineral water.

The radioactivity comes from radon gas -- the same stuff that accumulates in basements, a by-product of the decay of uranium -- dissolving in the water underground. Once in the air, the radioactivity dissipates quickly, with a half-life of about four days.

Nevertheless, for the sake of science, we took a walk over to the Saratoga Spa State Park and collected a few bottles from the Polaris spring, one that is known to be radioactive. We also took a sip (it's carbonated but pretty sulfurous, so you wouldn't want to drink it regularly anyhow). So far, no one is glowing in the dark.

The radiation detector wasn't a total loss: it came with a really enlightening manual about radiation safety, for perusal in your fallout shelter. This article from the World Nuclear Association is also basic enough for kids. You'll also find all kinds of fascinating information about radiation at Theodore Gray's Periodic Table.

I'm still planning to get a working Geiger Counter, and maybe a few odds and ends from United Nuclear.