Bendy Bones

What's this Science Bite about?

Make bones bend in this bite sized science experiment!

Find out what makes bones hard and strong and how you can soften them to tie them in knots!

Always remember to ask your parent or guardian to help you.

What you'll need

Some chicken bones and a glass containing vinegar

  • 1 large jar
  • some long, thin chicken bones – washed and clean
  • some vinegar

How to do the experiment

  1. Try bending a few of your chicken bones - what happens?
    Chicken bones in a jar containing vinegar.
    Put your chicken bones in the jar and fill with enough vinegar to cover the bones completely.

    Now leave the jar somewhere safe for 1 week.

  2. Now you can remove the bones from the vinegar.
    Bending a chicken bone with hands
    Try to bend them and see what happens now (be careful of any sharp edges!). Can you tie them into a knot or twist them into a strange shape?

    When you have finished playing with them either tie them up into a tangle, or make a picture with them. Leave them somewhere safe for a few days to dry. Once they have dried they will be permanently bent into shape!


Find out more...

Bones contain mineral called calcium. In your bones this is attached to carbon and oxygen atoms to make calcium carbonate. This calcium carbonate is what makes bones hard and strong. We get calcium from foods like milk and cheese. We also need to have vitamin D (found in oily fish and sunshine) in our diet to be able to use calcium in our food. When the bones are in the vinegar, the calcium carbonate and the vinegar (which is a weak acid) react. If you look at the jar over the week you will even be able to see the reaction taking place (look for small bubbles on the surface of the vinegar).

These bubbles are carbon dioxide gas, which is formed by the reaction between the calcium carbonate and vinegar. Without the calcium carbonate in the bones they become much softer. This is why we can bend them and tie knots in them. By leaving the bones out in the air they will become hard again.

Curriculum Links

Body systems and Cells

SCN 1-12a/ 2-12a

Properties and Uses of Materials

SCN 2-15a


Glasgow Science Centre