Mole ratio of barium

Polymerizations. The polymerizations were carried out in an argon atmosphere in capped glass bottles fitted with a neoprene rubber gasket inner liner. In charging the polymerizations, the order of addition of materials was solvent first, then metal alkyls, next the barium salt, and finally the monomer(s). The amount of metal alkyl charged was sufficient to titrate the acidic impurities present in the solvent and polymerization bottle, plus the calculated amount for initiation of polymerizations. The mole ratio of barium to metal alkyl(s) was based on the moles of total alkalinity of barium to the moles of carbon-metal assayed. Unless otherwise stated,... 

Mole Ratio of Barium t-Butoxide-Hydroxide to n-BuLi. 

Figure 4 shows that the amount of trans-1,4 structure is increased from 557, which is the trans-1,4 content of a polybutadiene prepared with BuLi alone in nonpolar solvents, to a maximum of about 807, trans-1,4 content for polybutadienes prepared at a mole ratio of barium salt to BuLi equal to 0.5. 

This barium salt contains about 9 mole 7, hydroxide ion. It is important to note that the vinyl content is not affected by an increase in the mole ratio of Ba/Li from 0 to 0.5. However, a further increase in the mole ratio above 0.5 results in a decrease in the trans-1,4 content and a corresponding increase in the vinyl content. 

For those hydrates that don t decompose thermally, the extent of hydration can be determined by weighing the solid sample before and after heating. The mass after heating is for the anhydrous salt, and the difference in the two masses gives the mass of water originally present. Moles of both the anhydrous salt and water can then be calculated, and the mole ratio of water to anhydrous salt can be determined. These ideas are illustrated with a hydrate of barium chloride, BaCl2 xH20. 

Little work has been published concerning the isolation of oligosaccharides following graded, acidic hydrolysis of heparin. Wolfrom and co-workers have studied the partial, acid hydrolysis of a carefully purified heparin. (Purification was effected through the benzidine salt and the neutral barium salt was fractionally precipitated from water. The less-soluble fraction, after conversion to the barium acid salt, had a N S ratio of 2 5 and 5 sulfate groups per tetrasaccharide period, consumed 1 mole of periodate per tetrasaccharide period, and was shown to be homogeneous by electrophoresis and by countercurrent distribution. The molecular... 

Scientists also use the simplest formula to represent one mole of an ionic compound. They often use the term formula unit when referring to ionic compounds, because they are not found as single molecules. A formula unit of an ionic compound represents the simplest ratio of cations to anions. A formula unit of KBr is made up of one ion and one Br ion. One mole of an ionic compound has 6.022 x 10 of these formula units. As with molecular compounds, the molar mass of an ionic compound is the sum of the masses of all the atoms in the formula expressed in g/mol. Table 1 compares the formula units and molar masses of three ionic compounds. Sample Problem F shows how to calculate the molar mass of barium nitrate. 

The ratio of moles of H2O to moles of BaCl2 is 2 1, so two moles of water are associated with one mole of barium chloride. The value of the coefficient X is 2 and the formula for the hydrate is BaCl2 2H20. What is the name of the hydrate The CHEMLAB at the end of this chapter will give you experience determining the formula of a hydrate. 

A. BaSOJ—The key to this type of problem is to imagine that you had a 100-gram sample of the substance, because this allows us to change % to grams. In this case, you would have 58.8 g of barium, 13.7 g of sulfur, and 27.5 g of oxygen. Next, you divide the mass of each element by its molar mass to find out how many moles you have of each. Finally, you reduce the number of moles to a simple whole number ratio, which becomes the subscripts for the formula. 

What is the ratio of moles of barium chloride to moles of water ... 

Since the Equation 1 has two moles of nitrate, we adjust to that convenience. Change the molecularity of barium to its equivalence, then set the total equivalence of barium and potassium to two, and find the factor by which to multiply all of the formulas molecularities to maintain their respective ratios of concentration. 

An aqueous precursorfor 0.75Pb(Zni/3- Nb2/3)O3-0.25BaTiOs solid solution was synthesized by Van Werde et al. (2001). They used acetates of lead and zinc, and Nb(V) peroxocitrato complex. The solution of lead zincate niobate was prepared by adding the compounds into aqueous solution of ammonium citrate. The aqueous solution was stable when pH was higher than 8 and the citrate acid/cation mole ratio was higher than 1.5. The aqueous precursor for barium titanate was prepared by using titanium(IV) peroxocitrato complex and barium acetate. They found that the solid solution of PZN and BT is crystallized as a perovskite phase at temperatures as low as 800°C. 

Take, as an example, the case of barium oxide which, as we will see, has barium cations in interstitial positions. The fraction of sites for those barium ions is given by the ratio of the quantity (number of moles) of barium ions in that interstitial position to the total quantity of interstitial positions, whether occupied or otherwise, in that same volume. Thus, we will represent that fiaction of sites as ... 

Zirconium sulfophenylphosphonate can be prepared by the reaction of a water soluble zirconium salt with sulfophenylphosphonic acid. This phosphonic acid has been described in patent literature [ref. 22], but diere is no evidence of its actual synthesis. We found that sulfophenylphosphonic acid can be syndierized by the reaction of phenylphosphonic dichloride with CISO3H or SO3. The reaction of phenylphosphonic dichlmide with excess CISO3H proceeds smoothly to m-sulfophenylphosphonic dichlmide at 150 °C and to the phosphonic acid on subsequent hydrolysis. Purification of the acid requires removal of excess sulfate by barium precipitation, followed by ion exchange to remove excess barium. For a sulfate-fiee synthesis, we tried the direct sulfonation of phenylphosphonic acid with liquid SO3- The sulfonation proceeds readily at 125 °C, with excess SO3 relative to stoichiometry. We found that 1 1 ratios of S03 phenylphosphonic acid are insufficient for complete sulfonation, even under forcing conditions, due to the competitive formation of mixed anhydrides of sulfophenylphosphonic acid and SO3, depicted in fig. 4. This competitive formation results in a consumption of greater than 1 mole of SO3 per mole of phenylphosphonic acid. These anhydrides are thermally stable but may be converted to sulfophenylphosphonic acid by hydrolysis however, this method also requires sulfate removal from the final product. 

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