Carbonate solution, composition

To a solution containing 0.1 Af of each of the ions Ag+, Cu+, Fe+ and Ca+4 is added 2 M NaBr solution, giving precipitate A. After filtration, a sulfide solution is added to the solution and a black precipitate forms, precipitate B. This precipitate is removed by filtration and 2 M sodium carbonate solution is added, giving precipitate C. What is the composition of each precipitate, A, B, and C ... 

Darkowski and Cocivera [94] investigated trialkyl- or triarylphosphine tellurides, as low-valent tellurium sources, soluble in organic solvents. They reported the cathodic electrodeposition of thin film CdTe on titanium from a propylene carbonate solution of tri-n-butylphosphine telluride and Cd(II) salt, at about 100 °C. Amorphous, smooth gray films were obtained with thicknesses up to 5.4 p,m. The Te/Cd atomic ratio was seen to depend on applied potential and solution composition with values ranging between 0.63 and 1.1. Polycrystalline, cubic CdTe was obtained upon annealing at 400 C. The as-deposited films could be either p- or n-type, and heat treatment converts p to n (type conversion cf. Sect. 3.3.2). 

Pt deposited on WS2-Ti02 mesoporous composites was used for visible-light production of H2 in the presence of Na2S as radical scavenger [188]. Pt-loaded mesoporous zirconium-titanium phosphates also displayed good photoactivity in hydrogen production from carbonate solution [189]. 

Absorption of COj with carbonate solutions in a tower packed with 1-in. Raschig rings, (a) Correction factor /i for temperature and liquid rate (6) correction factors ft and /> for composition. [Sherwood and Pigford... 

Beryllium Basic Carbonate. Add a saturated ammonium carbonate solution dropwise to 4-5 ml of beryllium sulphate. Explain the precipitation of a substance and its dissolution in an excess amount of the reactant. Write the equations of the reactions. Boil the solution. Explain the appearance of a precipitate when the solution is boiled. What is its composition ... 

Magnesium Basic Carbonate (Magnesia Alba). Add a sodium carbonate solution to a magnesium sulphate or chloride solution heated to 50 °C up to complete precipitation. What is the composition of the precipitate Filter off the latter, wash it with water, and dry it in a drying cabinet at 100-150 °C. Heat the filtrate up to boiling. What do you observe Write the equations of the reactions. 

Add an equal volume of a sodium carbonate solution to a cerium nitrate one, next add dropwise a potassium permanganate solution. What is the composition of the precipitate Write the equation of the reaction. 

Normal carbonates of vanadium are unknown. An unstable ammonium vanadyl carbonate, of composition 3(NH4)2C0S.7V02.5C02. 16H20, has been obtained in small, violet crystals by the addition of ammonium carbonate to a neutral solution of vanadyl sulphate.4... 

Amine reagents also extract thorium from carbonate solutions and the use of a primary amine, RNH3C1, where R = C10 to Cl3 alkyl, as a 20% solution in kerosene allowed the concentrations of impurities in the extracted thorium to be reduced by factors of 33.8 for UVI, 111.4 for MoVI, 18.9 for Zrlv and 6167 for Mg11.177 The extracted thorium species was shown to be of the composition (RNH3)4Th(C03)4(H20)x. Di(tridecyl)amine has been used to extract thorium from barren uranium process liquors in the Blind River plant in Canada147 and flowsheets for the recovery of lanthanides, U03 and high-purity Th(S04)2 from the Elliot Lake area in Ontario using Primene/isodecanol have been described.178... 

Studiengesselschaft Kohle m.b.H. (2) reported the effect of temperature on solubility level in supercritical gas. The solubility is highest within 20 K of the critical temperature and decreases as temperature is raised to 100 K above the critical temperature. At temperatures near the critical temperature, a sharp rise in solubility occurs as the pressure is increased to the vicinity of the critical pressure and increases further as the pressure is further increased. Less volatile materials are taken up to a lesser extent than more volatile materials, so the vapor phase has a different solute composition than the residual material. There does not seem to be substantial heating or cooling effects upon loading of the supercritical gas. It is claimed that the chemical nature of the supercritical gas is of minor importance to the phenomenon of volatility amplification. Ethylene, ethane, carbon dioxide, nitrous oxide, propylene, propane, and ammonia were used to volatilize hydrocarbons found in heavy petroleum fractions. 

Natural carbonate minerals do not form from pure solutions where the only components are water, calcium, and the carbonic acid system species. Because of the general phenomenon known as coprecipitation, at least trace amounts of all components present in the solution from which a carbonate mineral forms can be incorporated into the solid. Natural carbonates contain such coprecipitates in concentrations ranging from trace (e.g., heavy metals), to minor (e.g., Sr), to major (e.g., Mg). When the concentration of the coprecipitate reaches major (>1%) concentrations, it can significantly alter the chemical properties of the carbonate mineral, such as its solubility. The most important example of this mineral property in marine sediments is the magnesian calcites, which commonly contain in excess of 12 mole % Mg. The fact that natural carbonate minerals contain coprecipitates whose concentrations reflect the composition of the solution and conditions, such as temperature, under which their formation took place, means that there is potentially a large amount of information which can be obtained from the study of carbonate mineral composition. This type of information allied with stable isotope ratio data, which are influenced by many of the same environmental factors, has become a major area of study in carbonate geochemistry. 

Solid solution theory The chemical theories of primary importance to understanding factors controlling carbonate mineral compositions in natural systems are associated with solid solutions. Carbonate minerals of less than pure composition can be viewed as mixtures of component minerals (e.g., SrCC>3 and CaSC>4 in CaCC>3). If the mixtures are of a simple mechanical type then the free energy of formation of the resulting solid will be directly proportional to the composition of the aggregate. Thus, for a two component, a and b, mixture ... 

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