Percent relative saturation calculation

The air concentration, Cg, the seawater concentration, Ci, and the Henry s constant H (2) can be used to calculate the percent relative saturation S of a compound in the ocean with the equation... 

Note Percent relative saturation was calculated as [(Q///Cg) undersaturation. The symbols are as in Table VII. 

Helium contains 12% by volume of ethyl acetate. Calculate (a) the percent relative saturation and (b) the percent absolute saturation of the mixture at a temperature of 30°C and a pressure of 98 kPa. 

A gas leaves a solvent recovery system saturated with benzene at 50°C and 750 mm Hg. The gas analyzes, on a benzene-free basis, 15% CO, 4% O2, and the remainder nitrogen. This mixture is compressed to 3 atm and is subsequently cooled to 20°C. Calculate the percent benzene condensed in the process. What is the relative saturation of the final gas ... 

The Kelvin equation can be combined with the relative humidity, RH, if water is involved as the fluid relative humidity indicates how moist the air is. The amount of water vapor in the air at any given time is usually less than that required to saturate the air. The relative humidity is the percentage of saturation humidity, generally calculated in relation to the saturated vapor density. Relative humidity may be defined as the ratio of the water vapor density (mass per unit volume) to the saturation water vapor density, usually expressed in percent. Relative humidity is also approximately equal (exactly equal when water is assumed as an ideal gas) to the ratio of the actual water vapor pressure to the saturation water vapor pressure, RH = PJP°. The P° values corresponding to each temperature are given in tables which can be found in handbooks. If RH is measured in an experiment, then Pv can be calculated by using the saturation water vapor pressure tables and can be inserted into the Kelvin equation. 

Fig. 17. Ethane versus ethane content of associated gases from Magnolia undersaturated and saturated oils. Ethane percent has been calculated relative to C2+ components and pseudo-components (i.e. methane is not included). Samples have been mathematically cleaned in order to remove the effects of oil-based drilling mud contamination.

Humidity Equilibration. The clays were humidified at 25°C in desiccators using a series of eutectic salts. Each dessicator was controlled at a different relative humidity using one of the saturated salt solutions listed in Table II. The samples were weighed repeatedly until equilibrium (constant weight) was reached. After the spectra were obtained, the samples were broken into three aliquots, reweighed and dried for -24 hours at 105°C to obtain the dry weights of the clay, from which the water contents were calculated. The water contents, as percent dry weight of the clay, are also shown in Table II. 

Related Calculations. Do not confuse percentage humidity with relative humidity. Relative humidity is the ratio of the partial pressure of the water vapor to the vapor pressure of water at the temperature of the air, this ratio usually being expressed as a percent. Percentage humidity is the ratio of the actual humidity to the saturation humidity that corresponds to the gas temperature, which is also usually expressed as a percent. At all humidities other than 0 or 100 percent, the percentage humidity is less than the relative humidity. 

A mixture of nitrogen and acetone vapor at 800 mmHg total pressure, 25 C, has a percentage saturation of 80%. Calculate (u) the absolute molal humidity, (h) the absolute humidity, kg acetone/kg nitrogen, (c) the partial pressure of acetone, (d) the relative humidity, (e) the volume percent acetone, and (/) the dew point. 

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