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Sodium and lithium

CH3)2N]3P0. M.p. 4°C, b.p. 232"C, dielectric constant 30 at 25 C. Can be prepared from dimethylamine and phosphorus oxychloride. Used as an aprotic solvent, similar to liquid ammonia in solvent power but easier to handle. Solvent for organolithium compounds, Grignard reagents and the metals lithium, sodium and potassium (the latter metals give blue solutions). [Pg.203]

However, the peroxomonophosphate ion decomposes relatively rapidly ia aqueous solution. A mixture of peroxodiphosphoric and peroxomonophoshoric acids can be produced by treatiag a cold phosphoric acid solution with elemental fluorine (qv) (49). Peroxodiphosphoric acid is not produced commercially. Ammonium, lithium, sodium, potassium, mbidium, cesium, barium, 2iac, lead, and silver salts have all been reported. The crystal stmctures of the ammonium, lithium, sodium, and potassium compounds, which crysta11i2e with varyiag numbers of water molecules, have been determined (50). [Pg.94]

Properties. Most of the alloys developed to date were intended for service as fuel cladding and other stmctural components in hquid-metal-cooled fast-breeder reactors. AHoy selection was based primarily on the following criteria corrosion resistance in Hquid metals, including lithium, sodium, and NaK, and a mixture of sodium and potassium strength ductihty, including fabricabihty and neutron considerations, including low absorption of fast neutrons as well as irradiation embrittlement and dimensional-variation effects. Alloys of greatest interest include V 80, Cr 15, Ti 5... [Pg.385]

Metals — Several metals react with water and air with the extent of reactivity being dependent upon the physical state of the metal. The highly reactive metals such as lithium, sodium, and potassium are pyrophoric (i.e., they ignite spontaneously in air without an ignition source). In contrast, the less reactive metals such as magnesium, zirconium, titanium, aluminum, and zinc are highly pyrophoric only as dusts. [Pg.174]

Lithium, sodium, and potassium (alkali metals) react rapidly with water to release hydrogen (Hj) gas ... [Pg.174]

Krapcho and Bothner-By made additional findings that are valuable ii understanding the Birch reduction. The relative rates of reduction o benzene by lithium, sodium and potassium (ethanol as proton donor) wer found to be approximately 180 1 0.5. In addition, they found that ben zene is reduced fourteen times more rapidly when methanol is the protoi donor than when /-butyl alcohol is used. Finally, the relative rates of reduc tion of various simple aromatic compounds by lithium were deteiTnined these data are given in Table 1-2. Taken together, the above data sho that the rate of a given Birch reduction is strikingly controlled by the meta... [Pg.14]

TABLE 1-5 Effect of Iron on the Birch Reduction of Estradiol 3-Methyl Ether by Lithium, Sodium and Potassium" ... [Pg.21]

The alkynylation of estrone methyl ether with the lithium, sodium and potassium derivatives of propargyl alcohol, 3-butyn-l-ol, and propargyl aldehyde diethyl acetal in pyridine and dioxane has been studied by Miller. Every combination of alkali metal and alkyne tried, but one, gives the 17a-alkylated products (65a), (65c) and (65d). The exception is alkynylation with the potassium derivative of propargyl aldehyde diethyl acetal in pyridine at room temperature, which produces a mixture of epimeric 17-(3, 3 -diethoxy-T-propynyl) derivatives. The rate of alkynylation of estrone methyl ether depends on the structure of the alkyne and proceeds in the order propar-gylaldehyde diethyl acetal > 3-butyn-l-ol > propargyl alcohol. The reactivity of the alkali metal salts is in the order potassium > sodium > lithium. [Pg.68]

Acid resistance This property is best appreciated when the glass structure is understood. Most enamel frits are complex alkali metal borosilicates and can be visualised as a network of Si04 tetrahedra and BO, triangular configurations containing alkali metals such as lithium, sodium and potassium or alkaline earth metals, especially calcium and barium, in the network interstices. [Pg.740]

Most of the recent research focuses on proton, lithium, sodium and potassium batteries. This is not only for the reasons discussed above. The availability of a large variety of electrodes also plays an important role. Furthermore, high voltages rather than high currents are favorable from a practical point of view. [Pg.537]

Investigation of the configurational stability of allylmetals 2a, prepared by means of Rieke metals from geometrically pure l-chloro-2-decenes 1 a in THF, showed that the (Z)- and (ZT)-lithium, -sodium, and -potassium derivatives preserve the configuration of the precursors to a preparatively useful extent below — 90°C, — 50°C, and >0°C, respectively. For the pairs of 3,7-dimethyl-2,6-octadienyl derivatives (Z)- and ( )-2b, which differ less in their thermodynamic stability, the respective temperatures are — 60 °C, — 40 °C and >0°C124. [Pg.230]

In closely related studies, the molecular and crystal structures of lithium, sodium and potassium N,N -di(p-tolyl)formamidinate and N,N -di(2,6-dialkyl-phenyl)formamidinate complexes have been elucidated. These showed the anions to be versatile ligands for alkali metals, exhibiting a wide variety of binding modes. ... [Pg.196]

In general, the reaction can be performed only with organometallics of active metals such as lithium, sodium, and potassium, but Grignard reagents abstract protons from a sufficiently acidic C—H bond, as in R—C=C—H —> R—C=C—MgX. This method is best for the preparation of alkynyl Grignard reagents. ... [Pg.791]

One early attempt to organize the elements clustered them into groups of three, called triads, whose members display similar chemical properties. Lithium, sodium, and potassium, for example, have many common properties and were considered to be a triad. This model was severely limited, for many elements could not be grouped into triads. The triad model is just one of nearly 150 different periodic arrangements of the elements that have been proposed. [Pg.520]

Large bound monovalent cations, e.g. tetrabutylammonium ions, are too large to penetrate any of the hydration regions. However, the smaller lithium, sodium and potassium ions are able to penetrate the outermost hydration region of the neutralized polyacid and this is accompanied by volume increases (Figure 4.9). These cations are probably not site-bound but are mobile in the outer cylindrical region of hydration (Figure 4.10). [Pg.76]

Zirconium reduces almost all oxygen-containing salts. This is the case for alkali hydroxides (accidents with the lithium, sodium and potassium compounds) and zirconium hydroxide, lithium, sodium and potassium carbonates, alkaline sulphates sodium tetraborate and copper (II) oxide. This is true especially for oxidising salts such as alkaline chromates and dichromates, chlorates (accident with potassium salt) and nitrates (accident with potassium salt). [Pg.217]

The carbonates, sulfates, nitrates, and phosphates of the group IA and IIA metals are important materials in inorganic chemistry. Some of the most important compounds of the group IA and IIA elements are organometallic compounds, particularly for lithium, sodium, and magnesium, and Chapter 12 will be devoted to this area of chemistry. [Pg.367]

COSMOS [Cracking oil by steam and molten salts] A catalytic process for cracking petroleum or heavy oils. The catalyst is a molten mixture of the carbonates of lithium, sodium, and potassium. Developed by Mitsui and piloted in 1977. [Pg.73]

The ion lattice model of Ref.20, applied to metals, leads to the values of 360, 210, and 730 erg/cm2 for the 111 face of lithium, sodium, and aluminum, respectively, all of which crystallize in the face-centered cubic lattices. See also Ref.21. ... [Pg.15]

A third method of estimating solvent basicity is provided by the donor number concept 14 ). The donor number of a solvent is the enthalpy of reaction, measured in kcal per mole, between the solvent and a Lewis add such as antimony (V) chloride. (Other Lewis acids, such as iodine or trimethyltin chloride, may be used, but the scale most often reported is that for SbCl5.) Available values for the SbCls donor number have been included in Table 1. Plots of the Walden product versus solvent basicity (A//SbC1 ) for several solvents are shown for lithium, sodium, and potassium ions in Fig. 10 and for the tetraalkylammon-... [Pg.55]

The broader subject of the interaction of stable carbenes with main-group compounds has recently been reviewed. Accordingly, the following discussion focuses on metallic elements of the s and p blocks. Dimeric NHC-alkali adducts have been characterized for lithium, sodium, and potassium. For imidazolin-2-ylidenes, alkoxy-bridged lithium dimer 20 and a lithium-cyclopentadienyl derivative 21 have been reported. For tetrahydropyrimid-2-ylidenes, amido-bridged dimers 22 have been characterized for lithium, sodium, and potassium. Since one of the synthetic approaches to stable NHCs involves the deprotonation of imidazolium cations with alkali metal bases, the interactions of alkali metal cations with NHCs are considered to be important for understanding the solution behavior of NHCs. [Pg.8]

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]


See other pages where Sodium and lithium is mentioned: [Pg.300]    [Pg.484]    [Pg.377]    [Pg.378]    [Pg.131]    [Pg.735]    [Pg.32]    [Pg.104]    [Pg.116]    [Pg.123]    [Pg.536]    [Pg.230]    [Pg.53]    [Pg.701]    [Pg.710]    [Pg.711]    [Pg.220]    [Pg.213]    [Pg.100]    [Pg.4]    [Pg.53]    [Pg.748]    [Pg.13]    [Pg.100]    [Pg.361]    [Pg.26]    [Pg.60]   
See also in sourсe #XX -- [ Pg.193 ]

See also in sourсe #XX -- [ Pg.280 ]




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