## 1.3. Gas Properties

### 1.3.1. Gas Density

As mentioned before, density is defined as the ratio of mass per unit volume of a material. Using a real gas law yields the following equation for gas density at a prevailing pressure and temperature. Here, MW is molecular weight, R is the universal gas constant, and Z is the gas compressibility factor.

$ρ=PMWZRT$

(1.155)

In contrast with the liquid phase, the cubic EOSs give reliable gas densities. Therefore EOSs can be used as a suitable method for the determination of gas density.

#### 1.3.1.1. Theoretical Determination of Gas Density

For the determination of gas density at a specified temperature and pressure, the ...

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