Concentration of an ideal gas

Since the partial pressure of a gas in atmospheres is not the same as its concentration in molarity, the value of for a reaction is not necessarily equal to the value of K. However, as long as the gases are behaving ideally, we can derive a relationship between the two constants. The concentration of an ideal gas A is the number of moles of A (njf) divided by its volume (V) in liters ... 

Let us first find the distribution of a molecule concentration of an ideal gas in a uniform one-dimensional external force field. Consider the field acting on the molecules to be conservative and uniform. Choose a unique z-axis coinciding with the direction of a force vector, along which we shall examine the molecules distribution. 

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