Molal absolute humidity

Jf.d and -WaW are the molal absolute humidity at Tg and t y, respectively (lb-mole vapor/lb-mole gas), hc/kn is known as the psychrometric ratio. 

Calculate the concentration (in terms of absolute humidity and molal absolute humidity) and enthalpy per unit mass of dry gas of saturated and unsaturated gas-vapor mixtures. 

When operations involve changes in the vapor content of a gas-vapor mixture without changes in the gas content, it is convenient to use concentration units based on the unchanging amount of gas. The mass of vapor/mass of gas ratio is the absolute humidity, Y. If the quantities are expressed in moles, the ratio is the molal absolute humidity, Y. Under conditions where the ideal gas law applies,... 

If equilibrium has not been reached between a mixture of components, the condition is referred to as partial saturation. At partial saturation the gas mixture obeys real gas laws. There are several ways to express the concentration of a vapor in a mixture of gases. Most often, weight or mole fraction is used. Other definitions are relative saturation (relative humidity), molal saturation (molal humidity) and absolute saturation (absolute humidity). 

Humid air at 75°C, 1.1 bar, and 30% relative humidity is fed into a process unit at a rate of 1000 m /h. Determine (1) the molar flow rates of water, dry air, and oxygen entering the process unit, (2) the molal humidity, absolute humidity, and percentage humidity of the air, and (3) the dew point. 

The latest weather report includes the following statement The temperature is 78°F, barometric pressure is 29.9 inches, and the relative humidity is 87%." From this information, estimate the mole fraction of water in the air and the dew point ( F), molal humidity, absolute humidity, and percentage humidity of the air. 

Define relative saturation (humidity), molal saturation (humidity), absolute saturation (humidity), and humidity by formulas involving partial pressures of the gas components. 

In many respects the molal ratio is the more convenient, thanks to the ease with which moles and volumes can be interrelated through the gas law, but the mass ratio has nevertheless become firmly established in the humidification literature. The mass absolute humidity was first introduced by Grosvenor [7] and is sometimes called the Grosvenor 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. 

Notice that, unlike the absolute humdidity, the absolute molal humidity is independ-ent of the identity of the gas. ... 

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