Friday, April 29, 2011

CakeMate Hearts

If you're not making cupcakes, there's only so much you can do with Cake Mate Valentine's hearts.  After we had eaten our fill of the hearts a kind neighbor gave us, I wondered what we'd do with the rest.  "How about candy experiments?" a friend suggested.  Of course.




According to the label, these red hearts actually contain three dyes: Red 3, Red 40, and Yellow 6.  When we tried chromatography, the red heart dye separated into at least two different colors, a pink and an orange.


If the color table on www.red40.com is accurate, we found Red 3 ("cherry-red") and Red 40 ("orange-red").  Yellow may have been too faint for us to see (this is common), it might not separate from the other dyes in water (for instance, if it moves at the same speed in water as one of the other dyes), or it may only have been used in the pink candy which we did not test.

We also wondered if the hearts would sink or float.  Turns out they do both.


These two hearts were put in water at the same time.  One sank quickly, while the other floated for several minutes.  The floating heart had an air bubble trapped underneath, which probably helped the buoyancy.

Overall, the hearts floated at first, then sank, then returned to the surface as a dissolving mass of bubbles.

Friday, April 15, 2011

Easter Blue M's?

Easter M&Ms come in such pretty colors that when we got some last year, we were excited to experiment with them.  Sadly, the M&M colors were too faint for good chromatography--we could hardly see the colors on the paper, much less any separation.  So this year, we decided to concentrate on the m's themselves.


First of all, are these m's made of the same stuff as normal white m's?  Experimentation shows at least one difference: these m's seem to dissolve.

Blue streaks sinking down from the bottom of the m--dissolved blue dye?

That led us to the big question: do the blue m's float?  What about all those little bunnies and sheep?  Apparently so.



What about the speckles on the M&M eggs?


Yes, they float too.

Which leads me to my final question: how do they print the speckles on all sides of an oblong egg?  Alas, experimentation can't answer that one.

Friday, April 8, 2011

Do hearts float or don't they?

As I wrote previously, I've been wondering why Valentine's conversation hearts float if you leave them in water. My theory was that formation of air bubbles on the surface of the hearts made them float. So how could I test it?

Water has air dissolved in it. This air forms the bubbles you see when you start to heat water (as opposed to the bubbles formed by water vapor when water boils).*  You can remove most of the air by boiling the water. So I boiled a pan.

After the pan had returned to room temperature (I helped it along by letting the full pan of hot water sit in a cold water sink), I filled cups with 1/2 cup each of normal tap water and boiled water. Here's what happened:


In my tap water cup, bubbles quickly developed on the hearts.  In my boiled water cup, so few bubbles formed initially that I could still count them.  Two of my tap water hearts were floating within an hour.

Floating hearts covered with bubbles.

The hearts in boiled water, on the other hand, took much longer.  It was an hour and a half before one of the hearts was finally covered with enough tiny bubbles to start floating.

Why did the heart in boiled water float at all?  Because even though I boiled the water, the water was continually exposed to air.  I couldn't remove all the air unless I tried the process with vacuum equipment--which I don't have in my kitchen!

*For more information, visit The Engineering Toolbox.