Strontium ions, reactions

Reactions of strontium ions For the study of these reactions a 025m solution of strontium chloride SrCl2.6H20 or strontium nitrate Sr(N03)2 can be used. 

On boiling the precipitate appears again, because carbon dioxide is removed during the process and the reaction proceeds towards left. Barium and strontium ions react in a similar way. 

Non-isotopic carriers have their uses as may be judged by the following example. Sr is made from by an (n, p) reaction. The addition of a lead salt followed by fuming nitric acid precipitates lead and strontium together as nitrates and leaves the yttrium in solution. The lead, having thus acted as a non-isotopic carrier, may be precipitated as sulphide from a solution of the lead and strontium salts. Here again a hold-back carrier of inactive strontium ions is necessary to prevent adsorption of most of the Sr on the PbS. 

Strontium present in the atmosphere is in the form of wet or dry aerosols. The principal chemical species in the air is strontium oxide. Strontium oxide can undergo transformation to strontium ions by reaction with water. Strontium is dispersed by atmospheric cycling and subsequently deposited by wet deposition on the earth s surface. In surface and groundwater, strontium exists primarily as a hydrated ion. 

P. G. Morgan Franklin Institute) There seemed to be a temperature rise where your strontium carbonate itself decomposes. In other words, you superimposed some of the complexities of decomposition of strontium carbonate onto further reaction with titanium dioxide, and your supply of strontium ions and oxygen ions is continuously changing as decomposition proceeds. I think you could do one of two things to simplify this. You could either carry out the reaction between the carbonate and oxide in a temperature regime where the carbonate itself would not otherwise decompose, or you could just start with strontium oxide and titanium oxide to simplify things. 

Doddi, G., Ercolani, G., Pegna P.L., Mencarelh, P. Remarkable catalysis by strontium ion in Sfj2 and E2 reactions occurring in proximity to a crown ether structure. J. Chem. Soc. Chem. Commun. 1994, 1239—1240. 

For strontium-doped lanthanum chromites, the precipitation of SrO is not possible, because strontium ions are more stable in the perovskite stmctuie than the lanthanum ions. Lanthanum oxide, La203, is often precipitated instead of SrO. This causes the disintegration of sintered specimens at ambient temperatures by the volume change associated with the formation of lanthanum hydroxide, La(OH)3, due to the reaction of La203 with the water vapor in the air (Meadowcroft, 1969 Sakai et al., 1990a). The substitution of transition metals such as zinc (Hayashi et al., 1988), cobalt (Zhou et al., 1996), or vanadium (Larsen et al., 1997) have been used to improve the sintering of strontium substituted lanthanum chromite. The substitution of strontium and transition metals is often utilized for intercoimects of the planar type... 

Magnesium reacts slowly at lower temperatures to give the amide, as do all active metals this reaction is catalyzed by transition metal ions. Aluminum nitride [24304-00-5] AIN, barium nitride [12047-79-9] Ba2N2, calcium nitride [12013-82-0] Ca2N2, strontium nitride [12033-82-8], Sr2N2, and titanium nitride [25583-20-4], TiN, may be formed by heating the corresponding amides. 

The reaction of calcium iodide and strontium iodide and the ion in tetrahydrofuran (THF) followed by treatment with acetonitrile... 

Precipitation reactions, like all reactions, reach a position of equilibrium. Suppose, for example, solutions of Sr(N03)2 and K2Cr04 are mixed. In this case, Sr2+ ions combine with Cr042- ions to form a yellow precipitate of strontium chromate, SrCr04 (Figure 16.1). Very quickly, an equilibrium is established between the solid and the corresponding ions in solution ... 

The hydrolysis of dimethyl sulphate also provides a source of sulphate ion, and the reaction has been used for the precipitation of barium, strontium, and calcium as well as lead ... 

H. 8-Hydroxyquinaldine (XI). The reactions of 8-hydroxyquinaldine are, in general, similar to 8-hydroxyquinoline described under (C) above, but unlike the latter it does not produce an insoluble complex with aluminium. In acetic acid-acetate solution precipitates are formed with bismuth, cadmium, copper, iron(II) and iron(III), chromium, manganese, nickel, silver, zinc, titanium (Ti02 + ), molybdate, tungstate, and vanadate. The same ions are precipitated in ammoniacal solution with the exception of molybdate, tungstate, and vanadate, but with the addition of lead, calcium, strontium, and magnesium aluminium is not precipitated, but tartrate must be added to prevent the separation of aluminium hydroxide. 

The removal of inorganic salts from reaction mixtures afforded by polymeric materials may be simply and effectively accomplished by dialysis,166 178 after decomposition of remaining periodate with ethylene glycol130 131 or butylene glycol. 161 170 Alternatively, the iodate and periodate ions may be removed as such, or after reduction to free iodine. The iodate and periodate ions have been effectively precipitated by means of sodium carbonate plus manganous sulfate,6 or by lead dithionate,191 barium chloride,24 192 193 strontium hydroxide194 202 or barium hydroxide,203 204 lead... 

Another application is in the oxidation of vapour mixtures in a chemical vapour transport reaction, the attempt being to coat materials with a thin layer of solid electrolyte. For example, a gas phase mixture consisting of the iodides of zirconium and yttrium is oxidized to form a thin layer of yttria-stabilized zirconia on the surface of an electrode such as one of the lanthanum-strontium doped transition metal perovskites Lai Sr MO --, which can transmit oxygen as ions and electrons from an isolated volume of oxygen gas. 

Setting of the cements occurs by neutralisation, and involves initial formation of calcium or strontium polyacrylate and later formation of aluminium polyacrylate. There is also evidence for a later, slow reaction involving the ion-depleted... 

It has been observed in CVD as well as in ALD depositions that coordi-natively unsaturated y0-diketonate-type compounds may oligomerise or react with the environment and become less volatile [15,16,66,67]. This is a cause of instability, especially with larger and basic central ions such as strontium and barium. y0-diketonate-type chelates can be protected against oligomerisation and roomOtemperature reactions with moisture by adducting them with neutral molecules (Fig. 4) [68-71]. 

All but one of the reactions in Figure 4 lead to the formation of the soluble TiO + ion this seems consistent with the observed changes in the visible absorption spectrum of the solid electrode. It may also be that other titanium species are formed in solution, such as peroxytitanium complexes like H Ti05 We have no direct evidence as to the identity of the solution species at this time, and have limited the candidate corrosion reactions shown in Figure 4 to those for which thermodynamic data are readily available. Nonetheless, the fact that titanium is observed in the electrolyte only upon extensive photocorrosion (and then in smaller amounts than strontium) suggests that the initial photocorrosion process involves the loss of strontium from the SrTi03, with the formation of Sr(0Ac)2 or SrSO. ... 

This group contains the elements beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra). After the alkali metals, they are the second most active metals. Their electron configurations end with ns2. They become positive two charged ions by giving of their two valence electrons in chemical reactions. At room temperature, they occur in a monoatomic structure and they are solid at room temperature. Radium, a solid element, is the only radioactive member of this group. 

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