Chemical Articles

Chemical Association

A chemical bond is formed from molecules in the body both simple and complex. Chemical bonds are classified into 2 ie covalent bonds and non-covalent bonds. Furthermore, non-covalent bonds consist of ionic bonds, hydrogen bonds and Van Der Waals bonds. Here is a brief explanation of the chemical bonds that are formed.

The Covalent Association

A covalent bond is a chemical bond formed by the valence of each atom. This chemical bond can be studied again about its relation to valence through general chemistry books, or chemistry lessons in high school. Examples of chemical bonds that belong to covalent bonds are CO2 or better known as carbon dioxide. In this compound, this valence C is 4 and valence O is 2. Another chemical bond in the form of another covalent bond is the formation of a bond between a C atom of a divalent 4 and four H atoms each dival 1 to form CH4. This compound is known by the name of methane.

Hydrogen bond

The hydrogen bond is a chemical bond by one hydrogen atom with two different atoms. This chemical bond can be formed between uncharged molecules and charged molecules. Atoms that bind hydrogen more strongly are called other moderate hydrogen donors called hydrogen acceptor. Hydrogen bonds between water molecules (H2O). Notice that the oxygen atoms of the negative pole bond to the hydrogen at the positive pole of water.

Ion bond

The ion bond (or electrocovalent bond) is a type of chemical bond that can be formed between metal ions with non-metals (or polyatomic ions such as ammonium) through electrostatic attraction forces. In other words, the ion bond is formed from the attraction between two different ions of charge.

The ionic bond is a chemical bond formed between two clusters with opposite charges. This opposite charge is positive and negative. An example is a chemical bond that belongs to this ionic bond is the bond between the substrate and the enzyme. The optimal distance of this chemical bond is 28 Angstroms. Another chemical bond which is an ionic bond is a bond between a negatively charged carboxyl group attached to the substrate and a positively charged amine group to the enzyme.

Simply stated, the definition of ionic bonds is a bond between two kinds of ions (cations and anions) by Coulomb's electrostatic forces. However, for example for complex compounds [Fe (H2O) 6] 2+, Fe2 + central ions with H2O molecules are also largely bound by the electrostatic forces between central ions with fixed negative dipole generated by the traveling molecule. Since ionic bonds occur by means of electron transfer, it can be predicted that the alkaline and alkaline earth elements with the characteristic of ns (1-2) have a strong enough tendency to form ionic bonds with elements of halogen and oxygen groups with the characteristics of ns2 Np (4-5). The fact is encountered various types of ions with certain electronic configurations.

Types of Ion Species Species without valence electrons

H + hydrogen ions may be seen as the only example of a species without valence electrons, although their existence is stabilized in solvent solvent form, ie as hydronium ions, H3O +, in water.

Species with two valence electrons

Some fairly stable species with two valence electrons are hydride ions, H +, Li +, and Be2 +. These ions adopt the noble gas electronics configuration of He.

Species with eight valence electrons

The formation of stable species with eight valence electrons is like Na +, Mg2 +, F- and O2-. Thus, NaF, Na2O, MgF2, and MgO are examples of ionic species by adopting the nearest noble gas valence electron configuration, Ne.

Species with nine valence electrons

The fact that many d-type compounds are also ionic, of course the stability of its electronic configuration, especially the number of valence electrons, no longer follows the octet rule, but reaches eighteen. This species is commonly found in groups 11, 12 or even group 13 from period 4.

Species with "eighteen + two" valence electrons

This species generally consists of heavy elements. Element 81Tl is found as a Tl3 + cation of a stable valence electro 18 system. However, the Tl + cation was also found and even more stable than the Tl3 + cation. The stability of this configuration system is often also attributed to the full reality of all filled orbitals, typically known as the electronic configuration system "18 + 2" or by the term species with an inert pair of electrons. The elements of Ga, In, and Tl (group 13 of the periodic table), Ge, Sn, and Pb (group 14) and As, Sb and Bi (group 15) can form sequentially M +, M2 + and M3 + ions Typical with an inert electron pair, (4-6) s2.

Species with a wide range of valence electrons

These types of ions consist of d and f group transition elements having electronic configurations d and f not yet full. Generally, these ions have the outer electronic configuration of 8-18 ns2 np6 nd0-10 with n = 3, 4, 5. In addition, the transition group elements are known to form cations with various oxidation levels.