This is the mark of chemical reactions. Bonds in molecules are ruptured and new bonds form. And that is about the maximum amount of energy we can expect from combustion of any molecule. 6H 2 O produces 16 kJ of energy or heat per gram of glucose. This is a ball and stick representation of glucose C 6 H 12 O 6 .
Spheres are atoms, cylinders are bonds.
The model has the advantage of showing the molecule in three dimensions. Carbons are green, oxygens are red, hydrogens are silver. When we eat proteins, these large molecules are often broken down into their amino acids and then reassembled to form other proteins. Protein Model - Insulin Ball and stick model of a representative protein, insulin. On thing we can see by inspection is that proteins are complex molecules containing significant oxygen and nitrogen.