Meant Institute of Chemistry, phase, chemical reactions, quantum chemistry, Legal Chemistry, Industrial Chemistry

Chemical bond is the force that holds together of atoms in molecules or crystals. In many simple compounds, valence bond theory and the concept of oxidation numbers can be used to predict molecular structure and arrangement. Similarly, theories from classical physics can be used to predict many of the ionic structure. In a more complex compound / complex, such as metal complexes, valence bond theory can not be used because membutuhken deeper understanding of the basis of quantum mechanics.

Phase is the collection of state of a macroscopic physical system that is relatively serbasama both chemical composition and properties of physics (eg mass density, crystal structure, index of refraction, etc.). Examples of circumstances that we know is the phase of solids, liquids, and gases. Other circumstances such as phase plasma, Bose-Einstein condensation, and condensation of fermions. State phase of the magnetic material is paramagnetic, ferromagnetic and Diamagnetism.

Chemical reaction is the transformation / change in molecular structure. This reaction can produce molecules combining to form larger molecules, splitting the molecule into two or more smaller molecules, or penataulangan atoms in molecules. Chemical reactions usually involve the making or breaking of chemical bonds.

Quantum chemistry mathematically describes the basic behavior of matter at the molecular level. In principle, it is possible to describe all chemical systems using this theory. In practice, only the simplest chemical systems may realistically be investigated with quantum mechanics must be pure and approximation for most practical purposes (eg, Hartree-Fock, post Hartree-Fock, or density functional theory, see computational chemistry for more details) . Therefore, a deep understanding of quantum mechanics is not required for most fields of chemistry because of the important implication of the theory (particularly the orbital approximation) can be interpreted and applied with more simple.

In quantum mechanics (several applications in computational chemistry and quantum chemistry), Hamiltonan, or physical condition, the particles can be expressed as the sum of two operators, one associated with kinetic energy and the other with potential energy. Hamiltonan the Schrodinger wave equation used in quantum chemistry have no terminology for the spin of electrons.

Completion Schrodinger equation for the hydrogen atom gives the form of wave equation for the atomic orbitals, and the relative energies of orbitals 1s, 2s, 2p, and 3p. Orbital approximation can be used to understand the other atoms such as helium, lithium, and carbon.

The laws of chemistry is actually a law of physics that is applied in chemical systems. The most fundamental concept in chemistry is the mass conservation law which states that there was no measurable change in the number of substances during an ordinary chemical reaction. Modern physics shows that the actual energilah eternal, and that energy and mass are interrelated. Conservation of energy is directed to the importance of the concept of equilibrium, thermodynamics, and kinetics.

The chemical industry is one of the important economic activities. World's top 50 chemical producers in 2004 had sales of USD $ 587 billion with a profit margin of 8.1% and penegluaran engineering (research and development) of 2.1% of total chemical sales.