If standard conditions are taken to be 14.65 psia and 60°F.

B „ = 0.0282(;77/>) =0.00502(z77>)........................................................(32)

The equations are exact, and the calculated valúes of gas FVF are cireclly related to the aecuracy of the valúes of z factor used.Coefficienl of Isothermal Compressibility of Cas. The coefficíent of isothermal compressibility of gas is defined as

c K = -0!y)(dVldp)T .............................................................................(33a)

or cí = (l/5j?K35Jt/a/7)7...............................................................................(33b)

Eqs. 33 and 20 can be combined and placed on a pseudoreducedbasis5:

1

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