#Density equation plus

Table 2 - Grain densities for common rock-forming minerals Grain densities for common rock-forming minerals are shown in Table 2. Given a porosity and specific fluid, density can be easily calculated if the mineral or grain density is known. 8 is a fundamental relation used throughout the earth sciences to calculate rock density.

4, 5, and 6 for a rock made up of two minerals, m 1 and m 2, and two fluids, f 1 and fвЂ‰2, we find Where ПЃ mix is the density of the mixture ПЃ A is the density of Component A ПЃ B is the density of B A and B are the volume fractions of A and B respectively (and so B = 1в€’ A).Д®xpanding this into a general system with n components,ДЇor example, exploiting Eqs. The density of a composite such as rocks (or drilling muds) can be calculated from the densities and volume fraction of each component. Where M s, M d, M sat, M b, and M fl are the mass of the solid, dry rock, saturated rock, buoyant rock, and fluid, respectively. Similarly, the definitions of the standard densities associated with rocks then follows: porosity for sandstone, limestone, and dolomite. Densities of the two components are then calculated and summed to give the final answer.Fig. The water vapour pressure is then subtracted from the total pressure to give the pressure of the dry component of the parcel. In the first calculator, the vapour pressure of water vapour in saturated air at the nominated temperature is calculated and multiplied by the relative humidity to give the actual water vapour pressure.

#Density equation plus

The density of moist air is calculated as the sum of the density of the dry air component of the mixture plus the density of the saturated component of the mixture. The following tools allow you to calculate the density of moist air by knowing either the temperature, pressure and relative humidity OR temperature, dew point and pressure. There are a number of algorithms available for calculating vapour pressure but we shall use a polynomial developed by Herman Wobus. Air is said to be saturated when the temperature and dew point of the parcel are equal. The warmer the air the more moisture that it can hold. The amount of water vapour that a parcel of air can hold varies with temperature. The density of humid air can be calculated as the sum of the densities of the two gases, dry air and water vapour in proportion with their partial pressures. Whilst this may appear a bit odd at first this occurs because the molecular mass of water (18) is less than the molecular mass of air (29). The addition of water vapour to a mass of air makes it less dense. In the real world the air always contains some moisture. Water is a very light molecule and much lighter than the average weight of the molecules found in air. So a water molecule has a molecular weight of 18 (2 * 1 + 1 * 16 = 18). Hydrogen is the lightest element and has a molecular weight of one. Water is made up of two hydrogen and one oxygen atoms (H 2O). Given the mixture of gases found in air the average molecular weight of air is around 29. Oxygen has a molecular weight of 16 so an O 2 molecule has a molecular weight of 32.

Nitrogen has a molecular weight of 14 so a N 2 molecule has a molecular weight of 28. In the atmosphere around us we have air which is about 78% Nitrogen (N 2), about 21% Oxygen (O 2) and about 1% other gases. The gas constant is measure of the weight of the number of molecules of a gas. You can use the calculator below to work out other examples. The density of dry air can be calculated using the ideal gas law, expressed as a function of temperature and pressure:ДЄs an example let us calculate airВ density of dry air at sea level in international standard atmosphere conditions of pressure (1013.25 hPa or 101325Pa) and temperature (15 oC). This article describes the procedure toВ calculate air density given the temperature, dewpoint and pressure or temperature, pressure and relative humidity.В Included on the page are online calculators.