Presentation on theme: "What is carbon dioxide and how is it discovered? Joseph Black, a Scottish chemist and physician, first identified carbon dioxide in the 1750s. Carbon."— Presentation transcript:
What is carbon dioxide and how is it discovered? Joseph Black, a Scottish chemist and physician, first identified carbon dioxide in the 1750s. Carbon dioxide is an odorless, colourless gas, which is faintly acidic and non-flammable. Carbon dioxide is a molecule with the molecular formula CO 2.
Where on earth do we find carbon dioxide? Where on earth do we find carbon dioxide? Carbon dioxide can be found mainly in air, but also in water as a part of the carbon cycle.
Applications of carbon dioxide by humans Humans use carbon dioxide in many different ways. The most familiar example is its use in soft drinks and beer, to make them fizzy. Carbon dioxide released by baking powder or yeast makes cake batter rise. Some fire extinguishers use carbon dioxide because it is denser than air. Carbon dioxide can blanket a fire, because of its heaviness. It prevents oxygen from getting to the fire and as a result, the burning material is deprived of the oxygen it needs to continue burning
The part carbon dioxide plays in environmental processes Green plants convert carbon dioxide and water into food compounds, such as glucose, and oxygen. This process is called photosynthesis. The reaction of photosynthesis is as follows: 6 CO 2 + 6 H 2 O --> C 6 H 12 O 6 + 6 O 2 Plants and animals, in turn, convert the food compounds by combining it with oxygen to release energy for growth and other life activities. This is the respiration process, the reverse of photosynthesis. The respiration reaction is as follows: C 6 H 12 O 6 + 6 O 2 --> 6 CO 2 + 6 H 2 O
Carbon dioxide emissions by humans Carbon dioxide emissions by humans Due to human activities, the amount of CO 2 released into the atmosphere has been rising extensively during the last 150 years. Humans have been increasing the amount of carbon dioxide in air by burning of fossil fuels, by producing cement and by carrying out land clearing and forest combustion.
GreenHouse Effect Over the past century, the Earth has increased in temperature by about.5 degrees Celsius and many scientists believe this is because of an increase in concentration of the main greenhouse gases: carbon dioxide, methane, nitrous oxide, and fluorocarbons. Fears are that if people keep producing such gases at increasing rates, the results will be negative in nature, such as more severe floods and droughts, increasing prevalence of insects, sea levels rising, and Earth's precipitation may be redistributed
Carbon dioxide and health The primary health dangers of carbon dioxide are: - Asphyxiation. Caused by the release of carbon dioxide in a confined or unventilated area. This can lower the concentration of oxygen to a level that is immediately dangerous for human health. - Frostbite. Solid carbon dioxide is always below -78 o C at regular atmospheric pressure, regardless of the air temperature. Handling this material for more than a second or two without proper protection can cause serious blisters, and other unwanted effects. Carbon dioxide gas released from a steel cylinder, such as a fire extinguisher, causes similar effects. - Kidney damage or coma. This is caused by a disturbance in chemical equilibrium of the carbonate buffer. When carbon dioxide concentrations increase or decrease, causing the equilibrium to be disturbed, a life threatening situation may occur.
We can save energy by not leaving the Light on, we can take short showers,we can built in a solar heater so industries will not have to work a lot so that means less carbon dioxide, We can use a local bus or a bicycle to go somewhere and not the car We need to recycle paper because they come from trees and trees help us to get rid of Carbon dioxide,we can also plant more trees We can build more flats then houses so we can use the rest of the aria for plants and trees