Carbon dioxide (chemical formula CO2) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state. CO2 is a trace gas being only 0.038% of the atmosphere.
As a gas, CO2 is colorless and odorless and harmful to human health in concentration higher than 5,000 ppm. The first person to discover CO2 in gas form was Flemish chemist Jan Baptist van Helmond in the 17th century, and the properties of CO2 were further researched by Scottish physician Joseph Black in the 18th century. Carbon dioxide is formed by combustion and by biological processes. These include decomposition of organic material, fermentation and digestion. As an example, exhaled air contains as much as 4% carbon dioxide, or about 100 times the amount of carbon dioxide which was breathed in.
Today CO2 gas has many industrial uses and it can be found in many everyday products.
Multi-Industry Uses for Carbon Dioxide (CO2):
Carbon dioxide in solid and in liquid form is used for refrigeration and cooling. It is used as an inert gas in chemical processes, in the storage of carbon powder and in fire extinguishers.
Metals Industry:
Carbon dioxide is used in the manufacture of casting molds to enhance their hardness.
Manufacturing and Construction Uses:
Carbon dioxide is used on a large scale as a shield gas in MIG/MAG welding, where the gas protects the weld puddle against oxidation by the surrounding air. A mixture of argon and carbon dioxide is commonly used today to achieve a higher welding rate and reduce the need for post weld treatment.
Dry ice pellets are used to replace sandblasting when removing paint from surfaces. It aids in reducing the cost of disposal and cleanup.
Chemicals, Pharmaceuticals and Petroleum Industry Uses:
Large quantities are used as a raw material in the chemical process industry, especially for methanol and urea production.
Carbon dioxide is used in oil wells for oil extraction and maintain pressure within a formation. When CO2 is pumped into an oil well, it is partially dissolved into the oil, rendering it less viscous, allowing the oil to be extracted more easily from the bedrock. Considerably more oil can be extracted from through this process.
Food and Beverages Uses for Carbon Dioxide:
Liquid or solid carbon dioxide is used for quick freezing, surface freezing, chilling and refrigeration in the transport of foods. Carbon dioxide gas is used to carbonate soft drinks, beers and wine and to prevent fungal and bacterial growth.
Health Care Uses:
Carbon dioxide is used as an additive to oxygen for medical use as a respiration stimulant.
Carbon Dioxide: The Breath of Life
Many experiments have been conducted to determine the effects of atmospheric CO2 enrichment on plant growth and development. In the vast majority of these studies, vegetative productivity has been significantly enhanced by increases in the air’s CO2 content. The provocative report also describes a number of non-climatic effects of atmospheric CO2 enrichment that positively impact human health, including the concentration enhancement of various health-promoting constituents of food and medicinal plants. They tend to enhance people’s quality of life.
Carbon Dioxide in the Earth’ atmosphere and Influence of Climate Change
Carbon dioxide in air is considered to be a greenhouse gas because of its ability to absorb infrared light. The concentration of CO2 in the Earth's atmosphere has been increasing at a noticeable rate for much of the past century, human industrial activities are believed to be adding to the amount of "greenhouse gases" naturally present in the atmosphere. There are mounting proofs that following the industrial revolution of the 18th and 19th centuries, which commenced in Britain and has expanded to several parts of the world, the amounts of carbon dioxide, methane and other greenhouse gases in the atmosphere has increased somewhat. They could have been contributing to Global Warming
Climate Change is believed by scientists, that have been working in that area for years, to be producing or contributing to the severity of effects such as:
Winds and tornadoes/hurricanes becoming stronger
Glacier Melting/declining snow cover
Rising river flows and sea levels,
Decrease in water levels in ponds, lakes and other water bodies
Increasing precipitation,
Timing of lake and river freeze-up/break-up
Copenhagen Climate Concerns
Many people have expressed grave concerns about what was attempted to be accomplished when representatives of the nations of the world met in Copenhagen in early December 2009, seeking to acquire power to restrict the use of energy produced from coal, gas and oil in the guise of fighting global warming and averting the so-called climate crisis.
Carbon dioxide plays a major role as a component of the carbon cycle in which carbon is exchanged between the atmosphere, the terrestrial biosphere (which includes freshwater systems and soil), the oceans, and sediments (including fossil fuels). These interactions are complex and widespread. They undoubtedly can be, and are, influenced by many types of human activities, but the extent to which humans have impacted these processes, and will impact them in the future, remains the subject of much research and debate.
Zheng Shucheng 1000819858
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