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Learn about Carbon Dioxide

Learn about the chemical compound carbon dioxide, the various properties of carbon dioxide, the carbon dioxide formula, and what happens when Carbon dioxide is passed through lime water.

There are various types of elements and compounds found in nature that help sustain life. They include compounds of hydrogen, Nitrogen, Oxygen, etc. they are present in various concentrations. Carbon dioxide is one such compound.

Carbon dioxide is made from the combination of carbon and oxygen molecules. It is a greenhouse gas. Carbon dioxide is found in abundance in nature. It helps sustain life. However, if the quantity of carbon dioxide in the atmosphere increases, then it is harmful to all living creatures. The increase in the quantity of carbon dioxide in the air has led to climate change and global warming.

Carbon Dioxide

Carbon dioxide is one of the gasses that make up our atmosphere. It is a carbon compound that is inorganic in nature. It is made from a combination of carbon and oxygen atoms. A molecule of carbon dioxide is made of one carbon atom, which is double bonded to oxygen atoms. The bond here is covalent in nature. Hence, the carbon dioxide formula is CO2.

CO2 is a colorless gas with a sour taste. It also has a sharp and faint odor. 

The concentration of carbon dioxide in the atmosphere is 0.04%. It is soluble in water and hence is found in groundwater, lakes, glaciers, and seawater. It is the gas that we exhale when we breathe out after inhaling oxygen.

History of Carbon Dioxide

Carbon dioxide was first discovered when Jan Helmont burned charcoal in a closed area, and ash was formed in the end. As this ash was much less than the charcoal he burned, he suspected the rest of it was transformed into an invisible substance. This invisible substance was Carbon dioxide.

Further, Joseph Black discovered that this gas was higher in density than air and did not support fire.

Significance of Carbon Dioxide

Even though the concentration of CO2 in the atmosphere is not a lot, it is very important for life on earth.

  • CO2 is a component of the carbon cycle in which the exchange of carbon between the soil, ocean, rocks, and the biosphere takes place.
  •  Phototropic creatures like plants produce carbohydrates with the help of carbon dioxide and sunlight. And carbohydrates are a fundamental source of energy for many life forms on earth.
  • Carbon dioxide is produced as a by-product during the decomposition of the organic matter and fermentation of sugar.
  • Carbon dioxide absorbs the energy that comes to earth in the form of the sun’s rays. If it wasn’t absorbed by carbon dioxide, it would be lost.
  • Various nutrients like proteins, lipids, carbohydrates, and nucleic acids have carbon as their primary component.

Physical and Chemical properties of CO2

The following are the physical and chemical properties of carbon dioxide:

  • As discussed, the carbon dioxide formula is CO2. This means one carbon dioxide molecule is made up of two oxygen atoms bonded with one carbon atom.
  • CO2 molecules are centrosymmetric; no electric dipole moment is observed in them. Four vibrational modes are exhibited by carbon dioxide molecules.
  • At any pressure below 0.51795 Mpa, carbon dioxide does not have any liquid state. Carbonia is a solid form of carbon dioxide that is produced when heated. CO2 is supercooled at high pressure.
  • Carbon dioxide is produced during combustion reactions.
  • Carbon Dioxide instant relief odorless and colorless. However, it gives out an acidic and sharp odor in large quantities. 
  • Carbon dioxide is non-flammable gas which means it does not burn. The density of CO2 is higher than that of air. It is 1.977 g/ml.
  • CO2 molecules dissolve in water. However, the solubility will decrease as the temperature rises.

The Reaction of Carbon Dioxide with Lime Water

Let us look at what happens when carbon dioxide is passed through lime water.

Calcium hydroxide is commonly known as lime water. Its chemical formula is Ca(OH)2. 

When carbon dioxide is passed through lime water, it leads to the formation of white precipitate. The name of the residue is CaCO3. The solution appears to be milky. This reaction takes place as shown below.

Ca(OH)2 (aq) + CO2 (aq) -> CaCO3 (S) + H2O (l) 

This means an aqueous form of Ca(OH)2 reacts with an aqueous form of CO2, which results in the formation of CaCO3 in solid form along with water.

The above test is used for detecting the presence of hydroxide salts. It is a qualitative test.

Production of Carbon Dioxide

Following are the ways in which carbon dioxide is produced:

  • We can produce CO2 distillation from the air. However, this method is not efficient.
  • Another method for obtaining Carbon dioxide is decomposing limestone. The limestone is heated up to high temperatures for this.
  • Carbon dioxide is also produced when organic matter decomposes or when sugar is fermented for the making of wine and other things.
  • Aerobic organisms produce carbon dioxide while oxidizing fatty acids, carbohydrates, and proteins. Frequently Asked Questions:

Conclusion

The atmosphere is made up of many gasses and envelopes our earth. Carbon dioxide is one of those glasses. The Carbon dioxide formula is CO2. A CO2  molecule is made up of two oxygen atoms combined with a single carbon atom in a covalent bond. It is an inorganic compound.

CO2  dissolves in water and has a density higher than air. It turns milky when mixed with limestone. Carbon dioxide supports life as plants need CO2  in order to produce food and nutrients. However, the rising levels of carbon dioxide in the atmosphere have led to global warming and climate change.

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Frequently asked questions

Get answers to the most common queries related to the NDA Examination Preparation.

What is an acid?

Ans: A sour-tasting chemical compound that releases H+...Read full

What is a base?

Ans: A bitter-tasting chemical compound that releases OH̵...Read full

Common indicators used for acids and bases?

Ans: Blue and red litmus, methyl orange, phenolphthalein, red cabbage etc.

What is a neutralisation reaction?

Ans: Reaction in which an acid and base react to form salt and water as end products.

What is the pH value?

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