Re: followon: Where and what phases does our energy go through after we die?

Hi Edward,

Thanks for your question. I would phrase your sentence, "all matter is made up of energy", a little differently. It's more accurate to say that all matter contains energy. As was noted in the previous answer, energy is a difficult and fuzzy concept to define, but we can say that energy is required to bind matter together - and to break it apart.

Let's look at two examples. First, a nuclear reactor. Here, unstable radioactive atoms are disintegrating spontaneously. This releases energy in the form of heat, used to boil water and drive steam turbines. In this case, it's the energy that bound together the atomic nucleus which is released and transformed from one form to another (heat).

We can move up in scale from atoms to molecules - atoms of different types that are bound together. Here, energy is required to form the chemical bonds that hold the molecule together. That energy may also be released as heat when a chemical bond is broken. If a bond is stable, we may have to put in more energy to break it than we get back as heat: we call this an endergonic reaction. Other types of chemical bond are less stable and require just a small energy input - termed activation energy - to break. They then release more energy than was supplied - an exergonic reaction. This is why living organisms contain enzymes: enzymes are catalysts which lower activation energy and make chemical reactions (bond breaking or formation) more favourable.

So to answer your question: yes, our remains do retain energy, in the chemical bonds between atoms (in hair, which is made of protein, these are peptide bonds) and in the atoms which make up those molecules. And the energy used to form the chemical bonds came from what we ate. We can trace the energy back to plants, which transformed solar energy into the chemical bonds in sugar molecules and ultimately, to the process of nuclear fusion in the sun. So in a sense, we are all the products of a giant nuclear reactor!

If you'd like to find out more, search Google or Wikipedia for some of the terms that I've put in italics, or go to General Chemistry Online for some great chemistry resources.