Why can't we use carbon dioxide as a fuel source just like trees do?

Question

If we can use oygen as a fuel why can't we use carbon dioxide as a fuel like trees do?
Trees convert carbon dioxide into fuel and give off oxygen as a by-product. Is it possible for us to do this?

Answer 1

Technically we don't 'use' o2 as a fuel...we use it to oxidize fuels (carbon compounds, by and large). Likewise trees aren't 'using' co2 as a fuel, they're converting the carbon to a more energy intensive compound that they can use when the sun is not shining - the just happen to release o2 in the process (it's waste to them). We would have to completely change the metabolic process of every cell in our body to photosynthesize. I don't think anybody would really be able to survive such a transformation.

Answer 2

Carbon Dioxide is not the fuel or electron donor. Light is the energy source in photosynthesis and water is the electron donor. After water is ripped of its electrons, oxygen is produced. Carbon dioxide is then "fixed" or reduced (energy added to the CO2 - it is the electron acceptor) to create organic molecules necessary for life such as cellulose and glucose. Humans then use organic molecules as fuels (or electron donor ) with oxygen as the electron acceptor - creating water and CO2.

CO2 is never a fuel and is only an electron acceptor (plants) to make fuels for the plant and animals who eat it or CO2 is a byproduct of animals/microbes who eat organic materials

Answer 3

I've asked the same question before.

The problem is that photosynthesis is an inefficient process. Trees have all day to just stand there and soak up the sun. And they don't need to produce that much energy. What they do is amazing, but duplicating it is impractical.

Answer 4

because it doesnt have any propulsion or and fire power so to say- it is too light to use as a source of fuel hope that helped

Answer 5

the plants fix carbondioxide as carbohydrates.we need oxygen for all metabolic processes.