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					Elements Uranium ore ! Main article for this section are: Chemical elements Element is a group of atoms that have the same number of protons in the nucleus. This amount is called the atomic number elements. For example, all atoms have 6 protons in the atoms of the core is the chemical element carbon, and all atoms have 92 protons in its core is the element uranium atoms. Display elements are the most fit in the periodic table, which groups elements based on similarity of their chemical properties. List of elements by name, symbol, and atomic number is also available. [edit] Ion ! Main article for this section are: Ion Ions or charged species, or an atom or molecule that lost or gained one or more electrons. Positively charged cations (eg sodium cation Na +) and negatively charged anions (eg chloride Cl-) can form a neutral salt (eg sodium chloride, NaCl). Examples of polyatomic ions that do not split up during acid-base reactions are hydroxide (OH-) and phosphate (PO43-). [edit] Compounds ! Main article for this section are: chemical compounds The compound is a substance formed by two or more elements in definite proportions that determine its structure. for example, water is a compound containing hydrogen and oxygen with a ratio of two to one. Compounds are formed and broken down by chemical reactions. [edit] Molecules ! Main article for this section are: Molecule Molecule is the smallest and not divided from a pure chemical compound that still retains chemical and physical properties are unique. A molecule consisting of two or more atoms bound to one another. [edit] Chemicals ! Main article for this section are: Chemicals A 'chemicals' may be an element, compound, or mixture of compounds, elements, or compounds and elements. Most of the material we encounter in everyday life is a form of mixture, eg water, alloys, biomass, etc.. [edit] Chemical bonds Atomic orbital and molecular orbital electrons ! Main article for this section are: Chemical bonding Chemical bonds that hold a gathering force of atoms within molecules or crystals. In many simple compounds, valence bond theory and the concept of oxidation can be used to predict molecular

structure and composition. Similarly, theories from classical physics can be used to predict many ionic structures. 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. [edit] Being a substance ! Main article for this section are: Phase of matter Phase is a set of conditions a macroscopic physical system that is relatively good serbasama chemical composition and properties of phase of matter (the phase transition, crystal structure, index of refraction, etc.). Examples of circumstances that we know the phase is a solid, liquid, and gas. Other circumstances that phase eg plasma, Bose-Einstein condensation, and condensation Fermion. State phase of the magnetic material is paramagnetic, ferromagnetic and diamagnetic. [edit] Chemical reaction Chemical reaction between hydrogen chloride and ammonia to form a new compound ammonium chloride ! Main article for this section are: chemical reaction The chemical reaction is the transformation / change in molecular structure. This reaction can result in molecules 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. [edit] Quantum chemistry ! Main article for this section are: Quantum chemistry 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 in purely quantum mechanical approximation and should be done for most practical purposes (eg, Hartree-Fock, post Hartree-Fock or density functional theory, see computational chemistry for more details) . Therefore, a detailed understanding of quantum mechanics is not necessary for most chemistry, as the important implications of the theory (principally the orbital approximation) can be understood and applied in simpler terms. In quantum mechanics (several applications in computational chemistry and quantum chemistry), Hamiltonian, 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. Hamiltonian in the Schrödinger wave equation used in quantum chemistry have no terminology for the spin of electrons. Solving the Schrödinger equation for the hydrogen atom gives the form of the wave equation for the atomic orbitals, and the relative energies of the orbitals 1s, 2s, 2p, and 3p. The orbital approximation can be used to understand the other atoms such as helium, lithium, and carbon. [edit] Chemical Law ! Main article for this section are: Chemical law

Chemical laws are actually applied the laws of physics in chemical systems. The most fundamental concepts in chemistry is the law of conservation of mass states that there is no change in the number of substances measured during an ordinary chemical reaction. Modern physics shows that Energy is eternal, and that energy and mass are related. Conservation of energy is directed to the importance of the concept of equilibrium, thermodynamics, and kinetics. [edit] Chemical Industry The chemical industry is one of the important economic activity. Top 50 chemical producers in the world 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. [3]


				
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posted:1/22/2010
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