Chemistry is the study of the atomically and molecular structure of the universe. This basic science explains the composition of matter and how it reacts to other physical phenomenon such as temperature, light, magnetism and force. The origin of chemistry was the ancient science of alchemy.
Graphic representation of atom structure showing nucleus composed by protons and neutrons with attached electrons. The number of particles in the nucleus and electron cloud determine the atom classification or atomic number:Hydrogen, Gold or Sodium, as examples.
Chemical reactions are changes in the composition of matter by many processes. Different elements behave differently when exposed to each other and in the presence of different environments. The formation of molecules, solutions and compounds are through this process.