Engineering

Compounds are substances which are formed when two or more chemical elements are chemically bonded together. Compounds are found everywhere, from the water (H2O) which we drink, to the aluminium chloride we use as a deodorant. They consist of various atoms arranged in a specific structure, called molecules. Compounds are formed through two types of chemical bonding, covalent and ionic bonding. A covalent bond is formed when electrons are shared between atoms, whereas ionic bonds are formed through the attraction of oppositely (positive charge and negative charge) charged ions.

 

It is an element that is an essential to all life on Earth, yet in its purest form it can suffocate living organisms. Nitrogen is one of the most important elements on Earth – it can be found in all living systems and makes up around 78% of the Earth’s atmosphere. It is a constituent of protein and nucleic acids. In its gaseous form, nitrogen is colourless, odourless and generally considered inert. In its liquid form nitrogen is also colourless and odourless, and resembles water. Nitrogen was first recognised in 1772 by number of scientists; Carl Wilhelm Scheele, Daniel Rutherford, Henry Cavendish and Joseph Priestley, who all found that air was composed of three different gases, oxygen, carbon dioxide and another gas which they dubbed ‘foul air’ (nitrogen). Nitrogen was first recognised as an element by Antoine Laurent Lavoiser in 1786, and named nitrogen in 1790 by Antoine Laurent Lavoiser. Today, nitrogen is used in food preservation, explosives, and aids medical research.