What is the chemical formula of bone

Subject librarian chemistry

Schoolgirl with elimed chicken bones

The topic of bone structure offers the opportunity to use easily obtainable visual material (have the butcher cut open bones) and experiments to make the lessons lively and realistic. The name of the subject nature and technology can really be implemented here if technical applications are taken up.

Decalcified bone - elastic bone

Students are deeply impressed by the decalcified bone, which still has the same shape but has become elastic. It is therefore clear that the bone wall material must consist of at least two building materials (bone lime and bone cartilage). Since the elastic bone still has the same shape, these materials must be intimately connected to one another.

This principle is also used in technology for glass fiber or carbon reinforced plastics or for reinforced concrete. The aim of these composite materials is stability and elasticity.

Instructions for descaling chicken bones

Soak bones in hydrochloric acid overnight (mix conc. Hydrochloric acid and water in a ratio of 1: 3).

Experiments around carbon dioxide

In order for students to understand how this rubbery bone was made, it must be shown how lime dissolves in hydrochloric acid. This is shown in the test tube experiment with calcium carbonate powder, since the effervescence is particularly clear here and a clear solution remains.

The difference to dissolving sugar or salt must be made clear, dissolving lime is something different, since carbon dioxide (the effervescence is caused by a gas, introduce carbon dioxide here) is created from the lime, and so lime can no longer be dissolved.

In scientific work, the students can produce carbon dioxide themselves and find out the properties of carbon dioxide. The work case from ChemZ (student case type B) or from Microscale and more is ideal for this purpose.

During these lessons about the composition of the bone substance, one can clearly feel the enthusiasm of the lower school students for chemical topics. The students get excited about the phenomenon and eagerly take in the explanations.

Lightweight construction of the bone

In addition to the bone material, the lightweight construction of the bone with the trabecular structure or the type of long bone can also be taken up. Here, students can use a sheet of paper to build constructions that are particularly stable without being massive (e.g. corrugated cardboard or technical structures such as the Eiffel Tower, etc.)