Transitional Elements And Colored Ions

TRANSITIONAL ELEMENTS In the periodic system of elements, those included in the transition group are group B elements, starting from IB – VIIB and VIII. In accordance with the filling electrons in its subshell, this element is a d block element, namely elements with valence electrons located in the inner d subshell its electronic configuration. In this section, the transition elements that will be discussed are transition elements in period 4, which consists of scandium (Sc), titanium (Ti), vanadium (V), chrome (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), and zinc (Zn). 1. Properties of Metals All transition elements are metals, which are soft, shiny, and a good conductor of electricity and heat. Silver is a transition element which has the highest electrical conductivity at room temperature an copper is in second place. Compared with groups IA and IIA, elements Transition metals are harder, have higher melting points, boiling points and densities tall. This is because transition elements share electrons in the d shell and s, so that the bond becomes stronger . 2. Oxidation Number Unlike groups IA and IIA which only have numbers oxidation +1 and +2, transition metal elements have several oxidation number. Like vanadium which has oxidation numbers +2, +3, and +4. 3. Magnetic Properties Every atom and molecule has magnetic properties, namely para-magnetism, where the atom, molecule or ion can be slightly attracted by the fieldmagnetic because there are unpaired electrons in the orbitals and diamagnetic, where atoms, molecules or ions can be repelled by a magnetic field because all the electrons in their orbits are paired. Meanwhile, in general, transition elements are paramagnetic because they have unpaired electrons in their d orbitals. This paramagnetic property will become stronger if the number of unpaired electrons in the orbital increases. The metals Sc, Ti, V, Cr, and Mn are paramagnetic, while Cu and Zn are diamagnetic. Fe, Co and Ni are ferromagnetic, that is, they are in the same condition as paramagnetic, only in a solid state. COLORED IONS The energy levels of electrons in transition elements are almost the same, causing colors to appear in transition metal ions. This happens because electrons can move to higher levels by absorbing visible light. In the transition group, the 3d subshell that is not yet completely filled causes the electrons in that subshell to absorb light energy, so that the electrons are excited and emit light energy with a color that matches the color of the light that can be reflected when it returns to the ground state. For example, Ti2+ is purple, Ti4+ is colorless, Co2+ is red young, Co3+ is blue, and so on. Some uses of transition elements a. Scandium, used in high intensity lamps. b. Titanium, used in the aircraft industry and chemical industry (whitening paper, glass, ceramics and cosmetics). c. Vanadium, used as a catalyst in the manufacture of sulfuric acid. d. Chromium, used as a plating for other metals. e. Manganese, used in the production of steel and generally manganese alloysiron. f. Iron, used in electronic devices. g. Cobalt, used to make metal alloys. h. Nickel, used to coat metal to make it rust-resistant, makesmonel. i. Copper, used in electronic devices and jewelry. j. Zinc is used as a white paint ingredient, an antioxidant in the manufacture of car tires, and as an ingredient for coating television picture tubes.