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Carrie and I decided (beyond all reason!) to run a home-spun chemistry camp for Leo and one of his MineCrafting school friends, Connor. We decided to do this because Leo is in this difficult age where all the camps we can find are either too old for him or too young for him. And also because I like playing with chemicals; I had a home lab when I was in high school that had (beyond all reason!) all sorts of scary stuff, some of which you can’t even get now, including all three concentrated acids (Nitric, Sulfuric, and Hydrochloric), and a pound of metallic sodium!!

The camp went for three days, over the short 4th of July week. Each day was approximately dedicated to a different topic: Day 1 was approximately simple reactions and acids and bases, day 2 was polymers, and day 3 was energy. We had planned many experiments (realizing that we weren’t going to get to all of them), and the boys kept a lab notebook (of sorts).

By the way, Ada was out of day care this week too, and participated quite a bit, as you’ll see!

Here’s an approximate list of what we did, and some commentary about what worked and what didn’t. A bunch of pictures follow, and at the end I’ve listed experiments that we planned but never got around to for one reason or another. Carrie and I shared leading the experiments.

Day 1: Basic Chemistry:

  • Safety First: 1. Never eat anything; 2. Always wear safety goggles!
  • Properties of matter: Figure out which white powder is sugar and which is salt (without tasting them — see safety rule #1 above!); This worked quite well; we looked at the crystal structure under the microscope, dissolved them, burned them (or tried — salt melts at something like 1500C!), and observed how they changed the conductivity of water.
  • Carrie showed crystal structures, including minerals and rock candy. (The rock candy was a hit with Connor and Ada!)
  • Carrie also led a series of experiments on yeast production of CO2 that worked well, including varying the amount of sugar and temperature of the water.
  • I then did a demo of the difference between CO2 and O2 production from yeast (and other sources — tried to use the yeast-produced CO2, but didn’t work, so devolved to good old baking soda and vinegar!). This is led to our discussion of reactions and catalysis, showing the NaOH+Acetic Acid<->NaAc + H2O + CO2 [we didn’t end up balancing the equations, although I had intended to!], vs. H2O2 + Yeast -> O2 via catalase.
  • Finally we extracted the indicator from red cabbage and explored acids and bases, comparing (I would like to say “calibrating”, but we didn’t get too detailed about it!) the cabbage-based indicator against PH paper.
  • At the end of each day, Leo and Connor worked with the Education Edition of MineCraft, which has a chemistry mode. They supposedly built a laboratory, although mostly they just played MineCraft with one another — which is fine.

Day 2: Polymers

  • Slime the good old fashioned way, via Elmer’s glue (vinyl acetate) cross-linked by borax. (One of the important distinctions about this Chem Camp is that in addition to doing the experiments, we study the molecular structures and reaction equations. This is particularly interesting in the case of polymerization reactions.)
  • Carrie found a cool experiment where you put a certain sort of potato chip bag (Sunchips) in the microwave for just a couple seconds and it shrivels up due to the polymer being woven with metal; The microwave heats it, and causes the polymer to basically collapse.
  • Next we did the classic strawberry DNA extraction. (DNA being a polymer! Polymers also come back later in comparing cell membranes to bubbles.)
  • By far the most successful experiment was Carrie’s muffin baking series where they varied the amount of baking soda, baking powder, yeast, and sugar in a series of muffins. (This actually only has slightly to do with polymers — gluten a bit — more like a continuation of Day 1’s experiments with yeast, acids, and bases.) The muffins all came out, and were mostly edible, and it was completely clear that there were huge differences in rising and taste. (Ada, by the way, had great fun covering herself, Carrie, and the entire kitchen, with batter; See pics below!)
  • The rest of the day (up to the required MineCraft “work”) was spent making bubbles with dry ice. I had intended to actually do experiments on the amount of soap vs. various additives, esp. mineral oil, glycerol, and PEG (see below), and we did do a bit of this. Similarly, I had intended the polymer conceptual thread to run through the whole day — from basic polymers, to DNA, and finally to comparing “air” bubbles and “water” bubbles, in the form of cells (which we lysed earlier to get at the DNA). We did do a bit of discussion around this, but mostly the afternoon was bubble madness. (Shout out to my friend Edward Spiegel, moderator of the fandom Soap Bubble Wiki for guidance here!)

Day 3: Energy (this is the day we blow things up!)

  • We started out with a hold-over from yesterday’s polymer day. I ordered some J-Lube, which is high molecular weight PEG, so we played with that a bit, which was very icky (in a fun way), and it self-siphons, which is really mind-blowing!
  • Then to the topic of the day: Chemical Energy! I had a brain storm to explain reaction energy profiles (coordinate diagrams) using block towers: Build a tall stable structure, and then put in a little energy to knock them down and get back all that potential energy in the form of (mostly) noise! This was fun, but I don’t think they got the point.
  • Next we started burning things: Matches then magnesium then potassium permanganate and glycerine reactions. The idea was to demonstrate that when you cross the activation energy barrier, all hell breaks lose…and I think that they got that, after seeing ten incarnations. Also I wanted to demonstrate lots of examples of chemical potential energy. (I wanted to do the Sodium Acetate “warm ice” experiment, but I lost my pre-made sodium acetate hand warmers, and I know from experience that it’s very difficult to make these from a baking soda and vinegar reaction — it just never quite works out!)
  • We used infrared thermometers on various things, esp. the stove coils, and observed that at about 1000dF the coil starts visibly glowing. The boys liked that! (I had intended to get into the physics of black body radiation here, and then derive the Schrodinger equation…but we didn’t get that far … yes, I’m kidding!)
  • Carrie showed how ‘flavors’ in gums, candies, and other foods are created – in the case of gum, from sugar, citric acid (for a bit of zing), and esters to add smell. Everyone held their noses while they chewed the gum and could barely tell differences between the different gum flavors (except the fruit ones had citric acid and mint didn’t), but they were much closer to guessing once they uncovered their noses (still some ambiguity in which type of berry, but they correctly distinguished berry from orange and from mint gum flavors). The kids also noticed after uncovering their eyes at the end that the gum color helped provide a clue or ‘prime’ people as to the flavor.
  • Carrie also did a whole series over lunch on color, which sort of fit with a light and color theme. (I had purchased some high density diffraction grating paper with the idea that we would look at a lot of different examples and compare the spectral lines, but this didn’t work out too well. Everything pretty much just looked like a rainbow because there was too much ambient light.) Anyway, they prepared paints from fruits and veggies, and did some art with them, and Carrie tried to do some paper chromatography, which was supposed to go with my optical chromatography, but the paper chromatography was about as successful as the optical was. (Basically the red paint came out red on the paper, and the green came out green. I don’t think that these plant-based dyes are a mixture of colors as much as artificial colors, like pen ink, are.)
  • The last thing we did was chemiluminescence, using light sticks. I had intended to actually do this manually (that is, to use luminol, and mix it with H2O2 or chlorox) but it seemed un-necessary, given that I had a bunch of light sticks, and they do the same thing. I also had some really cool birthday candles that actually burn in colors; again, the idea was to get into atomic (or at least elemental) spectra, but again we didn’t get around to getting down to that level of detail.
  • The day ended in a water fight in the front yard, and, of course, the required MineCrafting.

We survived, although I’m somewhat surprised that things went as well as they did. I learned that 10-year-old-boys are … well, a major handful! I guess I kinda knew that from how difficult it is to get Leo to focus for more than 30 seconds on anything that isn’t what he happens to want to focus on (which is usually MineCraft!), but it was sort of shocking how it seemed like Ada had the most attention span of anyone in the room! 🙂

Carrie created a google drive folder with some of her cooking and color materials. Here’s a link to it.

As promised, pictures!

Some apparatus, safety goggles, and the red cabbage indicator:

 

 

Lab notebook scribbles:

 

 

Remains of burning things:

IMG_0509

 

Yeast-produced CO2:

 

 

Ada experimenting (with dirt, of course):

IMG_0569

 

Muffins (the results, and recording them):

 

 

Muffins (the preparatory stages):

 

 

Looking at the results of DNA extraction:

 

 

This is Science! (Standing, for some reason, in the remains of bubble play)

 

 

Coordinate (Reaction Energy) Diagram, and the block analog:

 

 

Preparing natural pigments:

 

Natural paint art and (mostly failed) chromatography:

What 10-year-olds do instead of being on task:

IMG_0782

 

Chemiluminescence:

 

 

Chem Craft:

 

 

Experiments we never got around to:

  • Precipitating casein from milk (polymers and state changes)
  • Lemon battery (energy)
  • Making Nylon-66 (polymers and state changes — decided this was too dangerous to do with 10-year-olds who were only partly on-task the whole time)
  • Cooking eggs (energy, polymers, and state changes)
  • Various dry ice experiments (state changes)
  • Electrolysis of water, and re-making the water (basic chemistry, energy)
  • Metal from soda cans – if you scratch it, the plastic lining on the inside of the can is scratched and the soda acid rusts the metal can. Electrolysis might speed that up.
  • Making polymer ice cream with konjac that you need to cut with a knife and fork.