Volume of equal masses

Since, however, the ratio of the absolute limiting densities is the ratio of the masses of equal volumes of the two gases when the latter are in the ideal limiting state, it follows from Avogadro s theorem that this is also equal to the ratio of the molecular weights Mi mi (lkfl oh M2 m2 Ow 0)1... 

Measure the masses of equal volumes of each liquid and calculate the density of water and cooking oil. Mix the water and oil together and observe the behavior of the liquids. 

Relative density Originally called Specific Gravity, ratio of mass of given volume of substance to mass of equal volume of water at 4°C. 

Let us turn to the surface layer of this same mixture being necessarily composed, as the remainder of the mass, of equal volumes of glycerin and of water, the ratio 1.54 found above can be looked at as hardly deviating from the average between the two values that would be obtained, on the one hand, if the surface layer only of the liquid were made of pure glycerin, and, on the other hand, if this same layer were made of pure water however, in this second case, the ratio would move away obviously... 

C05-0115. Consider two gas bulbs of equal volume, one filled with H2 gas at 0 °C and 2 atm, the other containing O2 gas at 25 °C and 1 atm. Which bulb has (a) more molecules (b) more mass (c) higher average kinetic energy of molecules and (d) higher average molecular speed ... 

Density is defined as the mass of a unit volume of material at a specified temperature and has the dimensions of grams per cubic centimeter (a close approximation to grams per milliliter). Specific gravity is the ratio of the mass of a volume of the substance to the mass of the same volume of water and is dependent on two temperatures, those at which the masses of the sample and the water are measured. When the water temperature is 4°C (39°F), the specific gravity is equal to the density in the centimeter-gram-second (cgs) system, since the volume of 1 g of water at that temperature is, by definition, 1 ml. Thus the density of water, for example, varies with temperature, and its specific gravity at equal temperatures is always unity. The standard temperatures for a specific gravity in the petroleum industry in North America are 60/60°F (15.6/15.6°C). 

It will be assumed here for simplicity that one parameter r (the radius in the case of a spherical liquid droplet) is sufficient to specify the size and shape of a particle. For solid particles (or liquid droplets), this assumption will be valid in spray combustion when either the particles are geometrically similar or their shape is of no consequence in the combustion process. Liquid droplets will obey this hypothesis in particular if they are spherical, which will not be true unless (1) they collide with each other so seldom that collision-induced oscillations are viscously damped to a negligible amplitude for most droplets, and (2) their velocity relative to the gas is sufficiently low. An alternative parameter to the radius is the mass of the droplet [10] the choice between this, the droplet volume, or the radius of a sphere of equal volume is a matter of individual preference. 

We have already ascertained that in the diffusion of a gas A into a solid or liquid B, the density of a volume element is practically unchanged, dg/dt = 0, because the mass of the gas absorbed is low in comparison with the mass of the volume element. If substance B was initially homogeneous, g = g x) = const, the density will also be unchanged locally during the diffusion process. We can therefore say a good approximation is that the density is constant, independently of position and time. Furthermore, measurements [2.76] have shown that the diffusion coefficient in dilute liquid solutions at constant temperature may be taken as approximately constant. Equally in diffusion of a gas into a homogeneous, porous solid at constant temperature, the diffusion coefficient is taken to be approximately constant, as the concentration only changes within very narrow limits. In these cases, in which g = const and DAB = D = const can be assumed, (2.328) simplifies to... 

It seems preferable to define density as above, by the mass of 1 ml. in g. (dimensions ml 3), although it has been defined1 as the ratio of the mass of any volume to the mass of an equal volume of water at its temperature of maximum density. The latter is not known with the necessary accuracy very often it is taken as 4°C. and the density is then formulated as D4. This ratio is really a specific gravity, but this is often understood to mean the ratio of the mass of any volume to the mass of an equal volume of water at the same temperature (not 4°) and is formulated as D. The specific volume is correspondingly defined here it is understood as the volume in ml. of 1 g. 

Two chambers of equal volume, each containing gas species A and B, are compressed into a single chamber. As a result, the average density of chamber 2 increases due to the compression. The mixture concentration in chamber 1 differs to that in chamber 2. That is, the concentration vector in chamber 1, Cj is different from 3. Since density is longer constant, it is not possible to express the mixture concentration in chamber 2 as a linear combination of concentration vectors Cj and 3. Instead, the mass of components A and B are conserved, and hence a mass balance may be performed. 

The ratio of the mass of aggregate to the volume the aggregate occupies in water is designated as density and its units of measurement are g/cm, Mg/m or kg/m. The mass of the volume of aggregates to the mass of an equal volume of water, normally at 25°C, or alternatively 23°C or 20°C, is designated as specific gravity. The value determined is dimensionless. 

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