In the wizarding world, Brackium Emendo is a healing spell that can be used to mend broken bones. In The Chamber of Secrets, Gilderoy Lockhart attempts this spell when Harry breaks his arm after falling during a Quidditch match.  Lockhart doesn’t do the spell properly, though, and ends up removing the bones instead of healing them, which makes Harry’s arm wobbly – like it has bendy bones. 

In our activity, we are going to use a chemical reaction to make a bone rubbery and bendy.  Bones are made of calcium and collagen. Calcium is the mineral that makes bones strong and collagen is a protein that makes them more flexible and less brittle.  We can remove the calcium by reacting it with the acetic acid in vinegar. Without calcium, the bone will be left mostly as the rubbery collagen and will be very bendable.  

Here is what to do, 

  1. Gather supplies
    • A bone (I am using one from a roasted turkey)
    • A beaker or jar
    • Vinegar
  2. Fill the jar with vinegar and soak the bone.
  3. Check on the bone periodically for the next several days. Depending on the size of the bone, it could take a week or longer for the calcium to react and the bone to turn rubbery. 
  4. When rubbery, rinse with water and observe how much it has changed.

Watch here: