Chemistry (earth science)

• Hundreds of millions of years ago huge quantities of living things died and were trapped in layers of rock, forming our fossil fuels of coal, oil and natural gas
• Sometimes the living things were trapped in mud deposits that got compressed into shale
• Tiny pockets of natural gas in these shales are now being exploited by fracturing the deep down rocks in a process called fracking
• Carbon dioxide released during respiration


  Cycled naturally
• Burning wood and agricultural waste


  Carbon is cycled naturally
• Biogas given off from food we throw into rubbish tips and from sewage works


  Carbon has been recently captured from the atmosphere and is simply returning to be used again in the natural cycle
• Burning fossil fuels


  Adds new carbon dioxide to the atmosphere
• You need to view the video on climate change environment 30 to explore the problems this is causing for our planet
• We use 90% of our food as a fuel and only 10% for building and repairing our bodies
• With fossil fuels, 90% are used as fuels and are combusted, and only 10% are used to make things such as plastic
• If we burn household waste including plastics, at least the oil has been used once or twice before it gets used as a fuel
• Better still is to use the plastic as a resource for making new plastics by recycling
• Carbon dioxide and oxygen dissolve in water, so there is a similar cycle that keeps life working in the oceans too
• Matter cannot be created, so nature continually recycles it
• We are re-learning to recycle matter