Uses of carbon dioxide
Carbon dioxide has four uses — and each of them follows directly from one of its properties.
1 — putting out fires
Because carbon dioxide (CO2) does not support combustion, it is used in fire extinguishers.
2 — in fizzy drinks
Dissolved in water, CO2 gives carbonic acid (H2CO3), which imparts a taste — so it is used to make soda water and carbonated soft drinks.
3 — dry ice
Cooled strongly under high pressure, CO2 becomes a solid. Warmed gradually it turns straight into a gas without melting — hence the name dry ice. Its temperature is about −77 °C, so it serves as a deep refrigerant in food preservation and is also used to make artificial rain.
4 — extracting iron
The carbon monoxide (CO) needed as the reducing agent in the extraction of iron is produced by reacting coke with CO2.
For extra knowledge
When writing out a balanced chemical reaction, the physical state in which each reactant and product exists during the reaction is often shown in front of it.
s = solid l = liquid
g = gas aq = aqueous
2Mg(s) + O2(g) → 2MgO(s)