An important endocrine gland producing hormones that affect metabolism and the calcium balance of the body.
A sphere is the set of points which are all within the same distance from a given point in space.
This animation demonstrates the components (vertices, edges, diagonals and faces) of the cube, one of the Platonic solids.
An exercise about the regular hexahedron built from unit cubes to help deepen your knowledge of cubes.
Farming techniques evolved with the development of human civilisation in the Middle Ages and the Modern Age.
An entertaining game about different views of spatial objects.
A cuboid is a polyhedron with six rectangular faces.
The Olympic Games, held in the town every 4th year after 776 BC made it one of the centres of ancient Greece.
Archimedes was one of the most brilliant Greek scholars of ancient times, who made his mark with military inventions as well.
The most important Neoclassicist building in France, completed in 1791, became the final resting place of many of France´s greats.
The city with advanced culture was the first settlement in history to have a citadel.
Addition is a reaction in which the molecules of two or more substances unite without the formation of a by-product.
Large-scale ammonia production requires high temperature and pressure and the presence of iron as a catalyst.
Ammonium chloride is the result of the reaction of ammonia and hydrogen chloride
The dissolution of zinc in hydrochloric acid produces hydrogen gas.
The solution of hydrogen chloride in water is called hydrochloric acid.
Knallgas is the mixture of hydrogen and oxygen. It will explode when ignited.
Common salt is dissolved by water: polar water molecules form a coat around the ions.
During freezing hydrogen bonds are formed between water molecules resulting in a crystal structure.
Polymerised ethylene is known as polyethylene, a type of plastic.