Carbon dioxide: it is a colourless, odourless, non-toxic gas found in the air. The average concentration of carbon dioxide in the air is 0.04%.
Importance and uses:
As a fire extinguisher - Carbon dioxide gas is used to extinguish fires as it stops the supply of oxygen necessary for the combustion process.
For photosynthesis - Plants take carbon dioxide and water from their surroundings and make food.
For beverages - Carbon dioxide gas is dissolved in water to give them a fizz and bubbly flavour. Soda and other soft drinks are manufactured in this manner.
For refrigeration - Carbon dioxide in solid-state also known as dry ice is used to refrigerate products during a journey.
In food - bakers yeast produces carbon dioxide gas that rises the dough and makes bread fluffy and soft.