A rare trivalent metallic element, found in gadolinite and other minerals. Symbol: Y, at. wt.: 88.905, at. no.: 39, sp. gr.: 4.47. Cf."rare-earth element."
Yttrium has a silver-metallic luster and is relatively stable in air unless finely divided. Turnings of the metal, however, ignite in air if their temperature exceeds 400oC. Yttrium oxide is one of the most important compounds of yttrium and accounts for the largest use. It is widely used in making YVO4 europium, and Y2O3 europium phosphors to give the red color in color television tubes.
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The interaction of orbitals on different atoms in the same region of space.
Mathematical method of treating particles on the basis of quantum theory, which assumes that energy (of small particles) is not infinitely divisible.
The material in a distillation apparatus that is to be distilled.
Effective Nuclear Charge
The nuclear charge experienced by the outermost electrons of an atom, the actual nuclear charge minus the effects of shielding due to inner-shell electrons.
Example: Set of dx2-y2 and dz2 orbitals, those d orbitals within a set with lobes directed along the x-, y-, and z-axes.
Nickel-cadmium cell (Nicad battery)
A dry cell in which the anode is Cd, the cathode is NiO2, and the electrolyte is basic.
Heat of Solution
The amount of heat absorbed in the formation of solution that contains one mole of solute, the value is positive if heat is absorbed (endothermic) and negative if heat is released (exothermic).
The temperature above which a gas cannot be liquefied, the temperature above which a substance cannot exhibit distinct gas and liquid phases.
Combination of symbols that indicates the chemical composition of a substance.
An element below and to the left of the stepwise division (metalloids) in the upper right corner of the periodic table, about 80% of the known elements are metals.
Involves a change in the composition of a nucleus and can evolve or absorb an extraordinarily large amount of energy.
High Spin Complex
Crystal field designation for an outer orbital complex, all t2g and eg orbitals are singly occupied before any pairing occurs.
Elements 89 to 103 (between lawrencium and actinium) on the periodic table. Only the first four have been found in nature in appreciable amounts. The remainder have been produced synthetically.
A colorless, nonvolatile solid, XeO3, explosive when dry: in solution it is called xenic acid.
Forces of attraction between a liquid and another surface.
A series of very closely spaced, nearly continuous molecular orbitals that belong to the crystal as a whole.
Nuclear Binding Energy
Energy equivalent of the mass deficiency, energy released in the formation of an atom from the subatomic particles.
Negative logarithm of the concentration (mol/L) of the H3O+[H+] ion, scale is commonly used over a range 0 to 14.
The combination of critical temperature and critical pressure of a substance.
Conduction of electrical current through a metal or along a metallic surface.
Strong Field Ligand
Ligand that exerts a strong crystal or ligand electrical field and generally forms low spin complexes with metal ions when possible.