Electrovalent compound

The word is also used to denote a unit in a solid crystal of an electrovalent compound such as NaCl in which each Na is electrically attracted by the surrounding six Cl" and each Cl" is electrically attracted by the surrounding six Na. The structure of such crystals is termed ionic to indicate that the crystal is not an aggregate of independent molecules. 

A comparison of this equation with the equations provided above points out that lead (IV) oxide is clearly not a base. The nature of metallic hydroxides varies according to the position of the metal in the reactivity series, as given in Table 6.3. Metallic hydroxides are electrovalent compounds, composed of metal ions, which are positively charged, and hydroxy ions, OTT. The number of OTT ions associated with one metallic ion is equal to the valency of the metal, e.g., Na+OH sodium is monovalent Ca2+(OTT)2 calcium is divalent. The metallic hydroxides form a very important series of compounds, and are known to have many uses both in the laboratory and in industry. 

Elecfrothermal atomization atomic absorption spectrometry, lithium, 36 54 Electrovalent compounds, high oxidation states of, stability, 5 10-11... 

Most organic compounds are low melting point solids, liquids or gases that are insoluble in water but soluble in organic (sometimes referred to as nonpolar) solvents such as ether, benzene and hydrocarbons. They do not conduct electricity. This is in contrast to ionic or electrovalent compounds with their bonding by electrostatic forces, which usually result in solids that are soluble in inorganic (sometimes referred to as polar) solvents such as water and that will conduct electricity when molten or in solution. 

Charged atoms or molecules are called ions. If Na and Cl are close together in solution, transfer of electrons between them easily occurs, and because of their opposing charges, they are mutually attracted, combining to form salt, NaCL The bond betwieen them is described as electrovalent. In solution in water, electrovalent compounds such as NaCI tend to separate into their component ions, and to join together again only in the solid material, thus ... 

Compounds containing ionic bonds are called ionic or electrovalent compounds. 1.2.1 Lattice Energy... 

It is known that metals in a biological milieu behave as positive ions and usually they form electrovalent compounds... 

COORDINATION COMPOUNDS. One of a number of types of complex compounds, usually derived by addition from simpler inorganic substances. Coordination compounds are essentially compounds to which atoms or groups have been added beyond the number possible on the basis of electrovalent linkages, or the usual covalent linkages, to which each of the two atoms linked donates one electron (o Form the duplet. The coordinate groups are linked to the atoms of the compound usually by coordinate valences, in which both the electrons in the bond are furnished by the linked atom of the coordinated group. The amines and complex cyanides are representative of coordination compounds. 

OXIDATION NUMBER. In its original and restrictive sense, the number of electrons which must be added to a cation to neutralize the charge. The concept has been extended to anions by assignments of negative oxidation numbers. Moreover, it has been further extended, first to all atoms or radicals joined by electrovalent bonds, and then to covalent compounds in which the shared electrons are distributed equally. For the broadest use of the concept, the expression oxidation state is often used. 

Because of the ease of removal of its single 4s electron (4.339 eV) and the difficulty of removing a second electron (31.66 eV) potassium is exclusively monovalent in its compounds, which are electrovalent (Some experimental work indicates that the potassium alkyls may be covalent, but even they form conducting solutions in other metal alkyls.)... 

Electrovalent bonds are formed between oppositely charged ions, and typically a metal donates electrons to a nonmetal. For example, sodium chloride (common salt, an important constituent of the body s fluids) is written as Na Cl. For sodium chloride only one electron is involved in the transfer and the molecular formula is written as NaCl. However, if sodium forms an ionic compound with oxygen, an oxygen atom needs two electrons to form an ion, so it will need to have two sodium atoms donating electrons ... 

Mode of Ionization of Salts.—Most ions, with the exception of hydrogen, hydroxyl and long-chain ions, have ion conductances of about 60 ohms cm. 2 at 25 , and this fact may be utilized to throw light on the mode of ionization of electrolytes. It has been found of particular value, in connection with the Werner co-ordination compounds, to determine whether a halogen atom, or other negative group, is attached in a covalent or an electrovalent manner. 

It can still be seen in mineralogical museums how Berzelius classified many compounds as adducts of oxides, as when alum is written K20 A1203 4 S03 24 H20 whereas it was later written KA1(S04)2 12 H20 and the crystal structure indicates only half of the water molecule oxygen atoms directly connected to aluminum K[A1(0H2)6](S04)2(0H2)6. Actually, the large majority of minerals are mixed oxides (and though these formulae derive from the precursor ideas of electrovalent bonding, considering calcium sulfate as an adduct CaO S03, they have the undoubted... 

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