Solution composition normality

To learn about normality and equivalent weight, concepts in stoichiometric calculations. 

Normality is another unit of concentration that is sometimes used, especially when dealing with acids and bases. The use of normality focuses mainly on the and OH available in an acid-base reaction. Before we discuss normality, however, we need to define some terms. One equivalent of an acid is the amount of that acid that can furnish 1 mole ofH ions. Similarly, one equivalent of a base is defined as the amount of that base that can furnish 1 mole ofOH ions. The equivalent weight of an acid or a base is the mass in grams of 1 equivalent (equiv) of that acid or base. 

The common strong acids are HCI, HNO3, and H2SO4. For HCI and HNO3 each molecule of acid furnishes one H ion, so 1 mole of HCI can furnish 1 mole of H ions. This means that 

1 mol HNO3 = 1 equiv HNO3 Molar mass (HNO3) = equivalent weight (HNO3) 

However, H2SO4 can furnish two H ions per molecule, so 1 mole of H2SO4 can furnish two moles of H. This means that 

The balanced equation tells us that the and OH ions react in a 1 1 ratio, so 8.75 X 10 mol of ions is required to neutralize (exactly react with) the 8.75 X 10 mol of OH ions present. 

Next we must find the volume (V ) of 0.100 M HCl required to furnish this amount of H ions. Because the volume (in liters) times the molarity gives the number of moles, we have 

Now we must solve for by dividing both sides of the equation by 0.100. 0,100 moHi 8.75 X lO moHi  

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Stoichiometry of Solution Reactions 491 Neutralization Reactions 495 Solution Composition Normality 497 Chapter Review SOI... 

Brass deposits normally contain 70-80% copper and 30-20% zinc the colour does not normally match solid brass of the same composition and may, moreover, vary with the operating conditions and solution composition. 

Water of various degrees of purity is the normal heat transfer fluid employed and a number of important problems with modern boiler water circuits are markedly influenced by solution composition. Most problems arise where solutions can concentrate and the compositions of such solutions can only be obtained by calculation from thermodynamic data. This paper concentrates on the kind of aqueous phase data which are currently most needed. Many of the needs overlap with those of geochemical interest. However, since Barnes (3) has recently reviewed the latter field, specifically geochemical needs will not be discussed. "High temperature" in this paper is generally taken to mean within about 100°C of the critical point of water (374 C), though some important problems which occur at lower temperatures are also considered. 

In this case, trace element and carrier occupy the same structural position both in the solid phase and in the melt and are subject to the same compositional effects in both phases (i.e., extension of the cation matrix in the melt and amount of anorthite component in the solid). Figure 10.9A shows the effect of normalization the conventional partition coefficient of Sr between plagioclase and liquid varies by about one order of magnitude under equal P-T conditions, with increasing anorthite component in solid solution, whereas normalized distribution coefficient D is virtually unaffected. Figure 10.9B shows the same effect for the Ba-Ca couple. 

Equilibrium relations in leaching usually are simpler than in liquid-liquid equilibria, or perhaps only appear so because few measurements have been published. The solution phase normally contains no entrained solids so its composition appears on the hypotenuse of a triangular diagram like that of Example 14.8. Data for the raffinate phase may be measured as the holdup of solution by the solid, K lb solution/lb dry (oil-free) solid, as a function of the concentration of the solution, y lb oil/lb solution. The correspond-... 

The characteristics of the neat soap aie controlled easily by accurately governing the composition of the alkaline solution used. Normal hydrolyzer neat soap contains about 69% actual soap, 30% water, and less than 1% NaQ, plus other stabilizers. Neat soap is a uniform, translucent, white, viscous fluid at 180-200 (82-93°C). 

A basic concept is that a given carbonate mineral will not dissolve in a solution that is supersaturated with respect to that mineral or precipitate from a solution undersaturated with respect to that mineral. If a solution is undersaturated with respect to all carbonate minerals, they may all dissolve with their relative dissolution rates determined by grain size, microstructure, and solution composition, among other factors. The idea that under universally undersaturated conditions mineral solubility may not simply control dissolution rates, even for grains of the same size, was confirmed by Walter and Morse (1985). They observed that relative dissolution rates in seawater could not be normalized directly to total surface areas, but rather depended strongly on microarchitecture (Figure 7.6). 

The usual objective of scanning probe microscopy techniques [41] is to provide images of a solid surface—normally topographic information— with up to atomic resolution. However, they can also be used to probe local solution composition and electrode reactions, as will be described. 

The behaviour of the glass electrode has also been examined.42-43 The glass-calomel electrode system yields stable and reproducible potentials which vary in the normal way with changes in hydrogen ion concentration. However, the EMF of the couple shifts several hundred millivolts as the solution composition changes from water to hydrogen peroxide. Table 1.2 summarizes the apparent and true pH of aqueous solutions of hydrogen peroxide. 

Data at pH 0.23, A data at pH 2.8. Solution compositions as in Figs. 47 and 48. Note that the potentials are given against the normal hydrogen electrode. 

Ferric Molybdate, Fe2(Mo04)j.42H20,is obtained as a j ellowish-brown precipitate when an aqueous solution of normal sodium molybdate is treated with ferric chloride. i If the di- or para-molybdate is so treated, a yellow precipitate, of composition Fe2O3.5MoO3.aq., separates rvith the tetramolybdate a pale yellow precipitate, of... 

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