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Group 4 is the second group of transition metals in the periodic table. It contains only the four elements titanium (Ti), zirconium (Zr), hafnium (Hf), and rutherfordium (Rf). The group is also called the titanium group or titanium family after its lightest member.
For alloys containing transition metal elements there is a difficulty in interpretation of the Hume-Rothery electron concentration rule, as the values of e/a values (number of itinerant electrons per atom) for transition metals have been quite controversial for a long time, and no satisfactory solutions have yet emerged. [9] [10]
As a metalloid the chemistry of silicon is largely covalent in nature, noting it can form alloys with metals such as iron and copper. The common oxide of silicon (SiO 2) is weakly acidic. Germanium. Germanium is a shiny, mostly unreactive grey-white solid with a density of 5.323 g/cm 3 (about two-thirds that of iron), and is hard (MH 6.0) and ...
118 chemical elements have been identified and named officially by IUPAC.A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z).
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
In 1923, Horace G. Deming, an American chemist, published short (Mendeleev style) and medium form periodic tables. [17] Each one had a regular stepped line separating metals from nonmetals. Merck and Company prepared a handout form of Deming's 18-column table, in 1928, which was widely circulated in American schools.
Metals in relatively high oxidation states tend to form covalent structures (e.g. WF 6, OsO 4, TiCl 4, AlCl 3), as do the more noble metals even in low oxidation states (e.g. AuCl, HgCl 2). There are also some metal oxides displaying electrical (metallic) conductivity , like RuO 2 , ReO 3 , and IrO 2 . [ 4 ]