Mixing gases

Pumping of liquids. Compression of gases Mixing (solids, liquids, gases possibly multiphase) Atomization, dispersion... 

Corollary.—If different ideal gases mix by diffusion so that the total volume of the mixture is equal to the sum of the volumes of the constituents, there is no evolution or absorption of heat. This result, wrhich may be regarded as an extension of the theorem of Joule, was also experimentally discovered by Dalton. 

In the metal partition type of cell a metal partition s placed between the anode and cathode. This parti-ion is insulated from the poles, is not so deep as the dectrodes, and is perforated on the lower edge with imall holes which, though reducing the electrical resist-mce, do not allow of the gases mixing. 

DIFFUSION FLAMES The flames seen in pyrotechnics are classified as vapour phase diffusion flames. The principal characteristic is that the fuel and oxidiser are initially separate (as finely powdered components). Combustion takes place when fuel and oxidiser crystals are subjected to high temperatures (from an igniter flame) the finely powdered components decompose, giving off columns of gas which mix by diffusion. The diffusion flame takes place in the zone where the gases mix. 

Gases mix. Gases mix better than liquids do and infinitely better than solids. So what s the relationship between the total pressure of a gaseous mixture and the pressure contributions of the individual gases Here s a satisfyingly simple answer Each individual gas within the mixture contributes a pcirtial pressure, and adding the pcirtial pressures yields the total pressure. This relationship is summcirized by Dalton s law of partial pressures for a mixture of individual gases ... 

The primary flame in the form of a dark-red taper is created by inflammable gases escaping from the bore. These gases mix with the air to form an inflammable mixture. If the temperature of the mixture is sufficiently high, it ignites at the end furthest from the muzzle (Fig. 190). 

Ecarnot passes his gases mixed witli a current of steam from a boiler, and with air supplied by a blast over surfaces of pumice-stone,... 

CAS. I. A slate of matter, in which the molecules move freely and consequently the entire mass tends to expand indefinitely, occupying the total volume of any vessel into w hich it is introduced. Gases follow, within considerable degree of fidelity, certain laws relating their conditions of pressure, volume, and temperature. Gases mix Ireely with each other, and they can be liquefied. 

The constant motion and high velocities of gas particles lead to some important practical consequences. One such consequence is that gases mix rapidly when they come in contact. Take the stopper off a bottle of perfume, for instance, and the odor will spread rapidly through the room as perfume molecules mix with the molecules in the air. This mixing of different gases by random molecular motion with frequent collisions is called diffusion. A similar process in which gas molecules escape without collisions through a tiny hole into a vacuum is called effusion (Figure 9.13). 

An interface is the area which separates two phases from each other. If we consider the solid, liquid, and gas phase we immediately get three combinations of interfaces the solid-liquid, the solid-gas, and the liquid-gas interface. These interfaces are also called surfaces. Interface is, however, a more general term than surface. Interfaces can also separate two immiscible liquids such as water and oil. These are called liquid-liquid interfaces. Solid-solid interfaces separate two solid phases. They are important for the mechanical behavior of solid materials. Gas-gas interfaces do not exist because gases mix. 

Mixture of gases A mixture of gases, say H2, N2 and 02 contributes one phase only as all gases mix freely to form a homogeneous mixture. 

All data were processed by a central computer to derive both temperature and species concentrations. The details of these computer fits are identical to those described elsewhere (10, 11) with the exception that a vibrational partition function correction was included in the analysis of the data. The absolute mole fractions of fuel, 0 CO, H2, C0 , and H2O were determined by flowing known concentrations of these gases mixed with known concentrations of N2 through the burner. A comparison of the intensity of the N2 Raman spectrum intensity to the Raman spectrum intensity of any of the other gases provided an absolute calibration for all laser Raman scattering flame studies. 

The ideal gas, consisting of molecules with zero volume that do not intera fulfills the conditions of solution ideality as a special case. When ideal gases mixed, there is no volume change of mixing, because the molar volume of mixture V B and the molar volumes of the pure species Vf are all equal to RT/... 

I. A stream of the combustible gases mixed with air is passed through a tube, the temperature of which is raised until the gases inflame.3... 

This is another name for mixing. It is usually used when gases mix they diffuse together. In liquids we usually say they mix or dissolve rather than diffusing. The diffusion is caused by the rapid movement of particles. 

Remove a wall between the two boxes and join them. Allow the gases to mix. For ideal gases, there is no change in gas volume when the gases mix so that ... 

PROBLEM A container has three gases mixed together at STP. The container has (by volume) 10% He, 40% neon, and 50% argon. What is the partial pressure of the three gases ... 

We know by experience that when two dissimilar gases are kept in two different compartments and if the partition between them is removed, the gases mix spontaneously and tend to make a homogeneous mixture. On the other hand, we never find that from a mixture of gases the molecules segregate to form two volumes of pure gases spontaneously. If this were to happen, entropy of the universe would have decreased hy an amount In TV +Ng In Ng). 

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