Oxygen

Properties of Oxygen

  • Oxygen is a colourless, tasteless and odourless gas. It makes up around 20.8% of the Earth’s atmosphere.
  • Oxygen is a non-metal and belongs to Group 16 (or Group VI) of the Periodic Table.
  • At standard temperature and pressure (STP), it exists as a diatomic molecule (O2).
  • Oxygen is paramagnetic, meaning it is attracted to the poles of a magnet, but does not remain magnetized. This is a result of its unpaired electrons.
  • Oxygen is slightly heavier than air and supports combustion.

Preparation of Oxygen

  • Oxygen can be produced in the laboratory by the decomposition of potassium chlorate (KClO3) using heat, often with a catalyst such as manganese dioxide (MnO2).
  • It can also be produced through the electrolysis of water.

Reactions Involving Oxygen

  • Oxygen readily reacts with most elements to form oxides. This reaction is called oxidation.
  • It is vital for respiration in animals and humans, as it enables the combustion of glucose in cells to release energy.
  • Oxygen is involved in the process of corrosion or rusting, where it combines with metals to form metal oxides.
  • In combustion reactions, such as burning of fuels, oxygen combines with other elements to produce heat and light.
  • Oxygen supports the combustion of substances, allowing burning to take place.
  • In higher concentrations, oxygen can be dangerous as it can promote and sustain fires.

Uses of Oxygen

  • Oxygen is used in respiration and it forms a vital part of the air we breathe.
  • It is also fundamental for combustion in various industries, particularly the steel industry where it is used in blast furnaces.
  • Oxygen gas is used in medicine, particularly in oxygen therapy, where it’s given to patients with breathing difficulties.
  • In its liquid form, oxygen finds applications as a rocket propellant.
  • It is used in the manufacture of a wide range of chemicals including nitric acid and hydrogen peroxide.

Oxygen in the Environment

  • Oxygen plays a key role in the ozone layer which protects the Earth from harmful ultraviolet (UV) radiation.
  • A reduction in the oxygen levels in water bodies can lead to oxygen depletion, which can kill marine and freshwater organisms.
  • Oxygen cycle involves the processes by which oxygen is generated and used within the Earth’s ecosystems.