Concentration of a solution defined

Write the equation relating osmotic pressure to the concentration of a solution. Define all the terms and specify their units. 

In practice, it is more convenient to predict the behavior of an ion, for any chosen set of conditions, by employing a much simpler distribution coefficient, which is defined as the concentration of a solute in the resin phase divided by its concentration in the liquid phase, or ... 

The detection limit is another value which is often quoted, and this may be defined in a variety of ways. The most widely accepted definition is that the detection limit is the smallest concentration of a solution of an element that can be detected with 95 per cent certainty. This is the quantity of the element that gives a reading equal to twice the standard deviation of a series of at least ten determinations taken with solutions of concentrations which are close to the level of the blank. 

Standardization was defined in Section 4.2 as a titration experiment in which the concentration of a solution becomes known to a high degree of precision and accuracy. In a standardization experiment, the solution being standardized is compared to a known standard. This known standard can be either a solution that is already a standard solution or an accurately weighed solid material. In either case, the solute of the solution to be standardized reacts with the known standard in the titration vessel. If the solution to be standardized is the titrant, then the known standard is the substance titrated, and vice versa. We will now describe these two methods and the calculations involved. 

Crystallization processes can be used for separation, purification, or concentration of a solute, or because a particular product needs to be used in solid form, or as a component of an analytical procedure. Common requirements for accomplishing these functions are that the crystals must be produced with a particular size distribution and having a specified shape and purity. Almost all crystallizer operating problems are defined in terms of the product not meeting one of these criteria. 

The octanol-water partition coefficient of a solute, defined as its concentration in the octanol-rich phase over its concentration in the water-rich phase at infinite dilution, is one interesting example of a liquid-liquid equilibrium coefficient. 

Radioactive decay with emission of particles is a random process. It is impossible to predict with certainty when a radioactive event will occur. Therefore, a series of measurements made on a radioactive sample will result in a series of different count rates, but they will be centered around an average or mean value of counts per minute. Table 1.1 contains such a series of count rates obtained with a scintillation counter on a single radioactive sample. A similar table could be prepared for other biochemical measurements, including the rate of an enzyme-catalyzed reaction or the protein concentration of a solution as determined by the Bradford method. The arithmetic average or mean of the numbers is calculated by totaling all the experimental values observed for a sample (the counting rates, the velocity of the reaction, or protein concentration) and dividing the total by the number of times the measurement was made. The mean is defined by Equation 1.1. 

Students will define solution and explain how to express the concentration of a solution using mass percent. 

Consider, for example, a system at temperature T with a solute concentration C, and define the equilibrium temperature of a solution having a concentration C as T and the equilibrium concentration of a solution at T as C. These quantities may be used to define the following approximate expressions of supersaturation ... 

The difference in concentration determining the diffusion of molecules across a membrane is the concentration just inside one side of the membrane minus that just within the other side. In Equation 1.7 the concentrations are those in the aqueous phases on either side of the membrane. Because membranes are quite different as solvents compared with aqueous solutions, the concentrations of a solute just inside the membrane can differ substantially from those just outside in the aqueous solutions. Therefore, a correction factor must be applied to Equation 1.7 to give the actual concentration difference existing in the membrane. This factor is the partition coefficient, Kjy which is defined as the ratio of the concentration of a solute in the material of the membrane to that in equilibrium outside in the aqueous phase (cj or cj), and so Kj is dimensionless. 

The concentration of a solute depends on the quantities of both the solute and the solution (or solvent). Molarity is defined as the number of moles of solute per liter of solution. Molarity is calculated by dividing the number of moles of solute by the volume of the solution in liters, or alternatively, by dividing the number of millimoles of solute by the milliliters of solution. Because molarity is a ratio, it can be used as a conversion factor to change the volume of solution into the number of moles of solute, or vice versa. 

The Ostwald partition coefficient, L, is a widely used and physically intuitive measure of gas solubilities and oil-water partition coefficients. It is defined as the ratio of concentrations of a solute between two phases at equilibrium. These two phases can be the ideal gas and a liquid phase, in which case the Ostwald partition coefficient gives the gas solubility, or two immiscible liquids - e.g., oil and water - in which case L is an oil-water partition coefficient. For the gas solubility of component 2 in liquid 1,... 

The partition coefScient is defined as the ratio of the concentration of a solute in the organic phase to its concentration in the water phase. This definition applies to the same neutral microspecies. However, many small molecules of pharmaceutical, agricultural and environmental interest may assume different protomeric and tautomeric forms, which increases the complexity of the above (simple) definition. Indeed, many small molecules contain moieties that ionize in water, thus contributing to a decrease in lipophilicity. The distribution coefficient, log D y, measures the pH-dependent distribution of drug in octa-nol-water phases at pH xy. 

A Danish chemist, S. P. L. Sorensen, proposed a convenient notation for the hydrogen ion concentration of a solution. He defined the negative log of the hydrogen ion concentration as pH. 

IUPAC recommendations for defining D are [7] distribution coefficient, D the ratio of the total (analytical) amount of a solute per gram of dry ion exchanger to its analytical concentration (total amount per cm ) in the solution concentration distribution ratio, D the ratio of the total (analytical) concentration of a solute in the ion exchanger to its concentration in the external solution (dimensionless) the concentrations are calculated per cm of the swollen ion exchanger and cm of the external solution volume distribution coefficient, D, the ratio of the total (analytical) concentration of a solute in the ion exchanger calculated per cm of the column or bed volume to its concentration (total amount per cm ) in the external solution. 

The concentration of a solution is defined as the number of moles of the solute in one litre or one cubic decimetre of solution. The unit of concentration is mol dm Solute is the term used for the substance which is dissolved. For more information on solution terms, see Unit 4.6. 

The normal concentration of a solution is defined by equations analogous to Equation 4-2. Thus, for a solution of the species A, the normality Cn(a> is given by the equations... 

The material in this chapter explains the relationship between the concentration of a solution component and its activity. The activity is monitored through the vapor pressure of the components, which are volatile for most of the examples considered. Thus, it is very easy to understand why the activity of a given component can also be defined as its escaping tendency. It is obvious from the fact that most solutions are non-ideal that the relationship between activity and concentration is not simple. When the solution is very dilute, Henry s law holds for the solute and Raoult s law for the solvent. Then the activity is proportional to the concentration over a finite concentration range which must be determined for each system. 

We specify the concentration of a solute in a bulk fluid as mass per unit volume denoted as c. As before, we designate the position of the interface so that there is no surface excess of the two pure bulk solvents. The concentration of surfactant, which we may denote as ca and cb, respectively, in the two bulk fluids, will exhibit a peak in the vicinity of the interface between and B. Hence, in a macroscopic continuum description, it is necessary to include a surface excess of surfactant on the interface. If we denote the local concentration as c(x, t), again defined as a mass per unit volume, then the total mass of surfactant per unit area of interface is... 

In chromatography, the physical act of a solute having different affinities for the stationary and mobile phases. Partition ratios, K, are defined as the ratio of total analytical concentration of a solute in the stationary phase, Cs to its concentration in the mobile phase CM. 

The concentration of a solution is the amount of solute present in a given quantity of solvent or solution. (For this discussion we will assume the solute is a liquid or a solid and the solvent is a liquid.) The concentration of a solution can be expressed in many different ways, as we will see in Chapter 12. Here we will consider one of the most commonly used units in chemistry, molarity (M), or molar concentration, which is the number of moles of solute in 1 liter of solution. Molarity is defined by the equation... 

A pOH scale analogous to the pH scale can be devised using the negative logarithm of the hydroxide ion concentration of a solution. Thns we define pOH as... 

Solution concentration is defined as the amount of solute dissolved in a given amount of solution. The concentration of a solution has a profound effect on the properties of a solution, both physical (melting and boiling points) and chemical (solution reactivity). Solution concentration may be expressed in many different units. Here we consider concentration units based on percentage. 

The concentration of a solution is defined as the amount of solute dissolved in a specified amount of solution. 

When the concentration of a solute is greater than about O.lmoldm", interactions between the solute molecules or ions are significant, and the effective and real concentrations are no longer equal. It becomes necessary to define a new quantity called the activity, which is a measure of concentration but takes into account the interactions between the... 

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