Fossil fuel consists of coal, oil, and natural gas that have been formed from the remains of plants and animals that died millions of years ago. What was the source of the energy used to produce the high-energy molecules in these fossil fuels?

The high-energy molecules found in fossil fuels, such as coal, oil, and natural gas, originated from the sun. The source of energy for the formation of fossil fuels can be traced back to the process of photosynthesis.

1.Photosynthesis: Plants, algae, and some bacteria undergo photosynthesis, a process where they capture sunlight and convert it into chemical energy. During photosynthesis, carbon dioxide and water are combined using solar energy to produce glucose (a high-energy molecule) and oxygen. The chemical equation for photosynthesis is:

6CO₂+6H₂O+light energy→C₆H₁₂O₆+6O₂

2.Biological Processes: The glucose produced through photosynthesis serves as a source of energy for living organisms. It is utilized in cellular respiration to produce ATP (adenosine triphosphate), which is the primary energy currency of cells.

3.Decomposition and Fossilization: When plants and animals die, their remains, including the carbon-rich molecules derived from photosynthesis, can accumulate in sedimentary environments. Over millions of years, these organic remains undergo decomposition, and under certain conditions (such as pressure and heat), they can be converted into fossil fuels like coal, oil, and natural gas through the process of fossilization.

In summary, the ultimate source of the energy stored in fossil fuels is solar energy, captured by plants during photosynthesis. The energy is then transferred through the food chain and preserved in the form of carbon-rich molecules in the remains of plants and animals, which later become fossil fuels.