Chapter 4 - Air and Water Flashcards
Oxygen
21%
Argon
0.9%
Carbon dioxide
0.04%
Separating gases in air
Air is cooled to below -200 degrees and fed into a fractional distillation column. Nitrogen is separated from oxygen and further distillation is used to produce pure oxygen and argon.
Oxygen reacts with substances to form
Oxides. This is known as combustion or oxidation.
Non metallic elements burn to form
Oxides produced as gases
Metallic elements burn to form
Solid oxides
Metal oxides and non metal oxides are
Basic and acidic.
Amphoteric
Oxides that behave like both acids and bases as they react and dissolve in acids but also react in alkalis like acids. Such as lead oxide or aluminium oxide.
Drinking water
Should contain only low levels of dissolved substances and microbes.
Sterilisation
Kills microbes in the water, chlorine is often used.
Pure water boils at
Exactly 100 degrees
Desalination
Seawater being converted into usable water for homes and industry.
Distillation
Boiling water to kill dissolved salts and microbes. Lots of energy needed to boil water as it’s very expensive to do on a large scale.
Filter jugs
Pass water through a filter cartridge containing activated carbon, an ion-exchange resin and silver as the carbon reduces chlorine levels and ion-exchange resin removes calcium, magnesium, lead, copper and aluminium ions. Silver nanoparticles discourage the growth of bacteria within the filter.
