Kamis, 09 Juli 2015


Team Author: Pearls Lombok, Lombok Tour Packages, Open Trip Lombok - paket wisata lombok In chemistry, the precious metal is a metal that is resistant to corrosion and oxidation. Examples of precious metals are gold, silver and platinum. Generally, precious metals have a high price, because it is rare and corrosion resistance. Precious metals are very difficult to react with the acid. Even so, some precious metals (eg gold) may be dissolved in aqua regia, a mixture of concentrated nitric acid and hydrochloric acid. All precious metals are members of the transition metal. The precious metal is used as jewelry and currency (gold, silver), rust-resistant material (steel) as a silver lining, or a catalyst (eg platinum). Precious Metals or commonly abbreviated as LM, also known as the trademark gold produced by PT ANTAM Tbk. tour lombok Silver is a chemical element in the periodic table that has the symbol Ag and atomic number 47. arms is derived from the Latin Argentum. A transition metal is soft, white, shiny, silver has the highest electrical and thermal conductivity across the contained metal and minerals and in free form. The metal used in coins, jewelry, tools table, and photography. Silver including precious metals like gold. Transition metals - paket wisata lombok Shape of the electron configuration of the transition metal atom can be written as [] ns2 (n-1) dm where d subshell have a greater energy than the valence s subshell. In the ion with two and three valence electrons, the opposite is true with s subshell has a greater energy level. The impact, such as Fe 2+ ion has no electrons in the subshell s: ion has the electron configuration [Ar] 3d6 compared with the electron configuration of the Fe atom, namely [Ar] 4s23d6. Elements in group 3 to 12 are now generally known as transition metal element, although elements of the La-Lu, Ac-Lr, and the group 12 (formerly called IIB) has different definitions in different authors.Many chemistry textbooks and the periodic table that included La and Ac as a third group elements and transition metals including the group, because the atoms have the outer electron s2d1 such as Sc and Y. The elements of Ce-Lu inserted into the lanthanide row (or " lanthanoid "according to IUPAC and Th-Lr in actinide lines. These two lines are together classified in the f-block elements or (in the old books) as a" transition elements in ". paket tour lombok Several chemistry textbooks incorporate La into the lanthanide and actinide Ac into. This classification is based on the similarity of the chemical properties, and defines fifteen elements in each row into a block-f though they acknowledge that the block-f can only be filled by a 14 element only. mutiara lombok The third classification defines that the elements consist of a block-f La-Yb and Ac-No and put Lu and Lr in group 3. This is based on Aufbau rule (or rules Madelung) in charging subshell electrons, where 4f populated before 5d (or 5f before 6d), so that f subshell is fully charged to the element Yb (and No), while Lu (and Lr) having the configuration [] s2f14d1. Nonetheless, La and Ac is an exception to the rule Aufbau with electron configuration [] s2d1 (not [] s2f1 as a prediction rule Aufbau) so that it is uncertain of its electron configuration is La or Lu (Ac or Bn) should be classified in a transition metal. Characteristics and properties harga mutiara There are several characteristics shared by transition elements that are not owned by other elements, which are caused by being filled in part of the subshell d. Among others are: formation of compounds whose color is caused by the transition of electrons the formation of compounds with a lot of oxidation numbers, due to the relatively low reactivity of the electron is unpaired d subshell the formation of several paramagnetic compounds caused by the d subshell electrons unpaired. Some compounds of main group elements are also paramagnetic (such as nitrogen oxide and oxygen). Colored compounds - harga mutiara Color in transition metal-containing compounds are generally caused by the transition of electrons in two types: charge transfer complex. An electron can jump from orbit to orbit ligand metal, forming ligant to metal charge transfer (LMCT). It can be seen easily when metal was in high oxidation numbers. For example, the color of the chromate ion, dichromate, and permanganate are of this type. Other conton is the mercury (II) iodide red larena LMCT transition. Transition metal to ligand charge transfer (MLCT) occurs when metal in a low oxidation number so easily reduced ligands. d-d transition. An electron hopping dadi one orbit d orbit to another. In the complex transition metal compounds, antarorbit d not have the same energy level. Pattern separation d orbit can be calculated with the crystal field theory. The degree of separation depends on the type of metal, the oxidation number, and the nature of the ligand. Actual energy level shown by Tanabe-Sugano diagram. paket wisata lombok In the centrosymmetric complex, such as octahedral, dd transitions violating the rules Laporte and only happened because the merger vibronik where molecular vibrations coincides with the transition dd. Tetrahedral complex has a pretty bright color due to a combination subshell d and p is possible if there is no center of symmetry, so that the transition is not purely dd. Oxidation number - lombok tour One characteristic of the transition metal is where these elements have more than one oxidation number. For example, the vanadium compounds are known to have begun -1 oxidation number of V (CO) 6- to +5 on VO43-. The maximum oxidation number in the first row transition metals equal to the number of valence electrons such as titanium (+4), and manganese (+7) but reduced in subsequent elements. In the second and third row there are ruthenium and osmium oxidation numbers +8. On compounds such as [Mn04] - and OsO4, transition metal elements to obtain a stable octet by forming four covalent bonds. The oxidation number is lowest in the compound Cr (CO) 6 (oxidation number zero) and Fe (CO) 42- (oxidation number -2) where the rule of 18 electrons obeyed. The compound is also a covalent. Ionic bonds are usually formed in the oxidation state +2 or +3. In the compound dissolved, the ions are usually bound with six water molecules are arranged in an octahedral. Magnetism - mutiara lombok Compounds in paramagnetic transition metal usually when there are one or more unpaired electrons in the subshell d. In the octahedral compound with electrons between four to seven in the d subshell, high spin and low spin may occur. Tetrahedral compounds such as [FeCl4] 2- is high spin crystal field splitting due to low so that the energy obtained from the electrons that are at a lower energy level is always less than the energy required to pair spin. Some compounds are diamagnetic. Which belong to this group is octahedral compound, low spin, d6, and d8 rectangular planar. Ferromagnetism occurs if a single atom is paramagnetic and the spin direction are arranged parallel to each other in crystalline materials. Ferrous metals and mixtures alniko are examples of transition metal compounds that are ferromagnetic. Anti-ferromagnetism is an example of magnetic properties formed from a special arrangement of a single spin in solid objects. Catalytic properties - harga mutiara Transition metals and their compounds are known to have catalytic activity of homogeneous and heterogeneous nature. This activity comes from the ability of transition metals to have more than one oxidation number and the ability to form complex compounds. For example Vanadium (V) oxide is known to separate the iron (the Haber process) and nickel (catalytic hydrogenation). The catalyst on the surface of a solid field to include the formation of a bond between the reactant molecules and atoms at the surface of the catalyst. This has the effect of increasing concentrations of the reactants on the catalyst surface and weakens the bond in a molecule that reacts (lowering the activation energy of the reaction). And also because of the transition metal oxidation number can change, so effective as a catalyst. Other properties - perhiasan mutiara As the name implies, all transition metal is a metal and an electrical conductor. In general, transition metals have a high density and melting and boiling points higher. It is due to the bonding of metal with electrons move easily, which causes cohesion which increases the amount of shared electrons. Nevertheless, the metal bracket 12 having a boiling point and lower melting Titih because subshell d elements to prevent bond dd. Mercury has a melting point -38.83 ° C (-37.89 ° F) and is liquid at room temperature. Transition metals can bind to form a variety of ligands. open trip lombok

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