Concentration of a mixture

Explosive limits The maximum and minimum concentrations of a mixture of gas, dust, or vapor in air or another gas which will explode if ignited. 

A worker exposed to an undetermined concentration of a mixture of sulfuryl fluoride and 1% chloropicrin for 4 hours developed nausea, vomiting, abdominal pain, and pruritis ... 

The absence of chromatographic separation makes MIMS a fast technique. It is advantageous in some applications where only select compounds are to be detected or the total concentration of a mixture is to be determined. For instance, the total concentration of trihalomethanes (THMs, including chloroform, bromoform, bromodichloromethane, and dibromo-chloromethane) in drinking water can be determined by MIMS in less than... 

Therefore, the molar concentration of a mixture at a location is equal to the sum of the molar concentrations of its constituents at that location. Molar concentration can also be expressed in dimensionless form in terms of mole fraction y as... 

A familiar example is the spectrophotometric determination of the concentrations of a mixture of n components by absorbance measurements at n different wavelengths. The coefficients a j are the e, the molar absorptivities of the components at different wavelengths (for simplicity, the cell path length, usually 1.00 cm, has been omitted from these equations). For example, for a mixture of three species P, Q and R, where absorbance measurements are made at X, A,2 and, 3 the equations are ... 

Figure 1. Paper chromatogram of different concentrations of a mixture of methyl parathion (A), Methyl Trithion (B), and carbo-phenothion (C) alsOy 1-gram aliquots of cleaned-up samples of control squash and wax beans...

Figure 5 shows the scans obtained from different concentrations of a mixture of five organophosphorus compounds dimethoate (A), mevin-... 

If you drink coffee, you know the difference between a strong cup of coffee and a weak cup of coffee. If you don t drink coffee, I am sure you can recall having a glass of weak iced tea, or some other powdered drink mix. When we talk about the strength of one of these drinks, we are really talking about the concentration of a solution. We will be learning more about concentration later on, but for now you should remember that you could vary the concentration of a mixture but not of a compound. 

Frey and Rodrigues [56] developed a method using the IAS theory and some approximations that yields explicit relationships for the adsorbed concentrations of a mixture with an arbitrary number of components. 

The effect of several concentrations of a mixture of 14 metals on the molybdenum absorption was studied (Table 13.11). Although insufficient work was done to relate the interference to specific metals, it is apparent that the method is subject to interference when other metals are present in a concentration appreciably higher than that of the molybdenum. That... 

The resulting concentration of a mixture from two separate mixtures. 

Dilute To lower the concentration of a mixture in this case the concentration of any hazardous gas in mine air by addition of fresh intake air. 

Explosive limits n. When combustible vapor is mixed with air in the proper proportions, ignition will produce an explosion. This proper proportion is called the explosive range. The explosive range includes all concentrations of a mixture of flammable vapor or gas in air, in which a flash will occur or a flame will travel if the mixture is ignited. The lowest percentage at which this occurs is the lower explosive limit and the highest percentage, the upper explosive limit. Explosive limits are express in percent by volume of vapor in air and, unless otherwise specified, under normal conditions of temperature and pressure. 

Further examples of cw-tra 5-isomerization comprise the irradiation of cyclododecatriene (CDT) with pyrex filtered light from a Hg lamp [14]. Starting from the m-isomer a steady concentration of a mixture containing in addition ctt- and cct/ccc-COT (the latter not separated) was produced (Scheme 3). Irradiation at shorter wavelength ( > 240 nm) gave major quantities of a vinylcyclodecadiene, the product from allylic bond fission. 

In this section, we will learn about molality and percent by mass, two additional ways to express the concentration of a mixture component. How a chemist expresses concentration depends on the type of problem being solved. 

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