Key points
Carbon dioxide is a A pure substance made from two or more elements which are chemically bonded in a fixed ratio. . Its molecules consist of one carbon atom joined to two oxygen atoms.
In the atmosphere, carbon dioxide is a Gases such as water vapour, carbon dioxide, and methane in the Earth’s atmosphere that trap heat..
We use carbon dioxide to make drinks fizzy and keep foods fresh.
The Chemistry of carbon dioxide
Get an introduction to the chemistry of carbon dioxide from a development engineer.
Structure and properties
At room temperature carbon dioxide is a colourless and odourless One of the three states of matter. Gases, like oxygen or helium, do not have a fixed shape and can expand to fill their container..
The carbon dioxide Two or more atoms which are strongly bonded together. The smallest particle of a substance that has all of the physical and chemical properties of that substance. is made up of one carbon (C) atom joined to two oxygen (O) atoms. This means it has a chemical formula is 䰿₂.
䰿₂ in the atmosphere
The amount of carbon dioxide in the The atmosphere is the layer of gases surrounding a planet. is maintained through a balance.
Processes that increase the amount of 䰿₂ in the air include:
- This is the scientific word for burning. It is where a substance reacts with oxygen from the air and transfers energy to the surroundings by heating and light. of petrol and diesel in cars
- The chemical process that occurs inside the cells of most living things, when glucose reacts with oxygen to produce carbon dioxide and water. of living things
Processes that decrease the amount of 䰿₂ in the air include:
- A chemical process used by plants to make glucose and oxygen from carbon dioxide and water, using light energy. Oxygen is produced as a by-product of photosynthesis. Algae subsumed within plants and some bacteria are also photosynthetic. by plants
- The process when a solute is mixed with a solvent and the solute breaks into much smaller particles and spreads out. in sea water
Carbon dioxide makes up less than 1% of the atmosphere; however, it is an important greenhouse gas.
This means that its molecules in the atmosphere absorb heat radiation from, keeping the Earth warmer than it would otherwise be.
For the past 100 or so years, carbon dioxide has been added to the atmosphere more quickly than it is removed. The extra carbon dioxide contributes towards The rise in the average temperature of the Earth's surface..
Global warming leads to climate change, including more frequent droughts and stronger storms.
Test your knowledge
Carbon dioxide quiz
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