Category Archives: Biology Experiments

Twisted Bones

We’re knuckle deep in a bone unit study right now.  Get it?  Knuckle deep!

Here’s an experiment we did over the past 24 hours, which amazed all of us:

Twisted Bones

2013-10-21 12.19.06For this experiment, you’ll need a baby food jar (or any size jar to fit your bone), a chicken or turkey bone (I was going to use a wishbone, but couldn’t find it.  I ended up using several smallish bones instead), baking soda, water, a bowl, rubber gloves, and 6% hydrochloric acid (I used 36% because that’s what Home Science Tools happens to have.  I diluted it with water).

Here’s what you do:

  1. First and foremost, know that hydrochloric acid is in fact…an acid.  Kids, let your parents handle this for you.  It’s corrosive and could be harmful if touched or swallowed. Parents, be sure to wear rubber gloves.
  2. Put your bone(s) in a jar along with the hydrochloric acid.
  3. Let it sit overnight.
  4. In the morning, put on rubber gloves, and transfer the bones into a bowl with a solution of 1 cup water, and 2 teaspoons baking soda.  Swish them around a bit to dilute and neutralize the hydrochloric acid.
  5. After a minute or two, take them out.  What do they feel like?

2013-10-21 16.36.57

Now, you can do something cool with the bones!  Are they long enough to tie into a knot?  Our weren’t so we twisted them together.

2013-10-22 10.36.39

 

Why does this happen?

The hydrochloric acid dissolves the mineral salts, leaving behind a bendy, cartilage remnant.