Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Metallic elements reactivity

Sulphur is less reactive than oxygen but still quite a reactive element and when heated it combines directly with the non-metallic elements, oxygen, hydrogen, the halogens (except iodine), carbon and phosphorus, and also with many metals to give sulphides. Selenium and tellurium are less reactive than sulphur but when heated combine directly with many metals and non-metals. [Pg.268]

The Group 13 metals differ sharply from the non-metallic element boron both in their greater chemical reactivity at moderate temperatures and in their well-defined cationic chemistry for aqueous solutions. The absence of a range of... [Pg.224]

Boron is a hard metalloid with pronounced nonmetallic properties. Aluminum is a light, strong, amphoteric, reactive metallic element with a surface that becomes passivated when exposed to air. [Pg.719]

Many years ago, geochemists recognized that whereas some metallic elements are found as sulfides in the Earth s crust, others are usually encountered as oxides, chlorides, or carbonates. Copper, lead, and mercury are most often found as sulfide ores Na and K are found as their chloride salts Mg and Ca exist as carbonates and Al, Ti, and Fe are all found as oxides. Today chemists understand the causes of this differentiation among metal compounds. The underlying principle is how tightly an atom binds its valence electrons. The strength with which an atom holds its valence electrons also determines the ability of that atom to act as a Lewis base, so we can use the Lewis acid-base model to describe many affinities that exist among elements. This notion not only explains the natural distribution of minerals, but also can be used to predict patterns of chemical reactivity. [Pg.1505]

Recently, metal cluster catalysts composed of two different metallic elements are of interest from both scientific and technological points of view because of their interesting physiochemical properties [46, 47]. Bimetallic clusters are known to exhibit specific reactivity. Their catalytic efficiency is also controlled by their size. [Pg.157]

Sodium is a very reactive metallic element for example, it liberates hydrogen gas when treated with water. Chlorine is a yellow-green, choking gas, used in World War I as a poison gas. Contrast these properties with those of the compound of sodium and chlorine—sodium chloride—known as table salt. [Pg.8]

In the list of reactivities of metals, Table 7-1, are all alkali metals more reactive than all alkaline earth metals, or are all elements of both groups of metals more active than any other metals ... [Pg.126]

A number of reactions between metals (or metals and semi-metals) may be carried out by dissolving the elements in a suitable solvent , technically also termed a flux . The solvent may also act as a reactant and be involved in the formation of the compound (reactive solvent, reactive flux). Several fluxes, ranging from simple metallic elements up to complex substances have been used. [Pg.575]

Other commonly employed redox electrodes are metals such as copper, cobalt, silver, zinc, nickel, and other transition metals. Some p-block metals such as tin, lead and indium can also function as redox electrodes. However, s-block metals such as magnesium do not make good redox electrodes since the elemental metal is reactive and forms a layer of oxide coating, which leads to poor reproducibility, poor electronic conductivity and electrode potentials that are difficult to interpret, (see Section 3.3.1). [Pg.39]

Cerium is a grayish/iron-colored, very reactive metallic element that is attacked by both acids and alkalies. Pure cerium will ignite if scratched with a knife, but it can be combined safely with many other elements and materials. It is relatively soft and both malleable and ductile. [Pg.280]

Berkelium is a metallic element located in group 11 (IB) of the transuranic subseries of the actinide series. Berkelium is located just below the rare-earth metal terbium in the lanthanide series of the periodic table. Therefore, it has many chemical and physical properties similar to terbium ( Tb). Its isotopes are very reactive and are not found in nature. Only small amounts have been artificially produced in particle accelerators and by alpha and beta decay. [Pg.325]

As a final example of a group of elements with similar properties, the metallic elements lithium, sodium, and potassium have such low densities that they float on water and are so highly reactive that they spontaneously burn by extracting oxygen from the water itself These light metals form strong alkalis and are appropriately called the alkali metals. You should locate each of these columns of similar elements, as shown in Figure 1-1, on the periodic table. [Pg.10]

For chalcogenide thin films it is possible to use elemental S, Se, Te as precursors provided that the other source is a volatile and reactive metal. ZnS deposition using elemental zinc and sulphur was the first ALD process developed [4]. Therefore for precursors other than metals, the reactivity of elemental chalcogens is not sufficient. For other precursor types, including halides, 6-diketonates and organometalHcs, simple hydrides, such as H2S, H2Se and H2Te, have typically been used as a second precursor. [Pg.131]

Reactions other than Lewis acid-base associations/dissociations are frequently observed wit donor molecules, leading notably to solvolysis, oxygen or sulfur abstraction, insertion reaction and carbon-carbon coupling reactions. The tendency to form metal-element multiple bonds i remarkable in this respect the activation of dinitrogen by tantalum or niobium is unique. Th formation and chemistry of constrained reactive metallacycles open another promisin fast-developing area, on the frontier with organometallic chemistry. [Pg.588]

Aluminum is a light, strong, amphoteric, reactive metallic element... [Pg.822]

Unlike the metallic elements, halogens become less reactive going down the periodic table because of their generally decreasing electron affinity. Thus, their reactivity order is F2 > CI2 > Br2 > I2. Fluorine often reacts violently, chlorine and bromine somewhat less so, and iodine often sluggishly. [Pg.227]

Silicon and germanium as elemental substances are found only in the diamond-type form. The reluctance of Si and Ge to enter into pre-p bonding prohibits a graphite-type structure as a plausible allotrope. These are rather more reactive than diamond the weaker Si-Si and Ge-Ge bonds make disruption of the lattice kinetically easier. Tin occurs in both a metallic form (white tin) and a covalent (diamond-type) form the latter is slightly more stable at low temperatures. Lead forms only a metallic elemental substance. [Pg.267]

Oxidation-reduction reactions (redox reactions) determine the chemical fate of many contaminants in groundwater and process water. Measuring the ORP (redox potential) enables us to evaluate the mobility and reactivity of non-metallic elements (sulfur, nitrogen, carbon) and metals in process water and to assess the types of redox reactions that take place in groundwater. We also use the ORP measurement as a well stabilization indicator in groundwater sampling. [Pg.168]

The metallic elements are all potentially very reactive towards air, water and most elements, but Be and Mg form passivating oxide films. Elemental magnesium is manufactured in large... [Pg.66]


See other pages where Metallic elements reactivity is mentioned: [Pg.125]    [Pg.338]    [Pg.76]    [Pg.541]    [Pg.140]    [Pg.22]    [Pg.30]    [Pg.107]    [Pg.235]    [Pg.52]    [Pg.75]    [Pg.359]    [Pg.482]    [Pg.338]    [Pg.247]    [Pg.125]    [Pg.4]    [Pg.460]    [Pg.30]    [Pg.296]    [Pg.36]    [Pg.227]    [Pg.405]    [Pg.315]    [Pg.343]    [Pg.392]    [Pg.248]    [Pg.159]    [Pg.57]    [Pg.386]    [Pg.69]   
See also in sourсe #XX -- [ Pg.80 ]




SEARCH



Elemental metallic

Elements metals

Elements reactivity

Elements, metallic

Metallic elements metals

Metals elemental

Metals reactivity

© 2024 chempedia.info